0001715768-22-000028 | 10-K | XBRL Viewer

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Cover - USD ($)	12 Months Ended
Cover - USD ($)	Mar. 31, 2022	Jun. 21, 2022	Sep. 30, 2021
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Mar. 31, 2022
Current Fiscal Year End Date	--03-31
Document Transition Report	false
Entity File Number	000-55832
Entity Registrant Name	Transphorm, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	82-1858829
Entity Address, Address Line One	75 Castilian Drive
Entity Address, City or Town	Goleta,
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	93117
City Area Code	805
Local Phone Number	456-1300
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Trading Symbol	TGAN
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
ICFR Auditor Attestation Flag	false
Entity Shell Company	false
Entity Public Float			$ 91,838,504
Entity Common Stock, Shares Outstanding		56,588,042
Documents Incorporated by Reference	None.
Entity Central Index Key	0001715768
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY
Amendment Flag	false

Audit Information	12 Months Ended
Audit Information	Mar. 31, 2022
Auditor Information [Abstract]
Auditor Name	Marcum LLP
Auditor Location	Chicago
Auditor Firm ID	688

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2022	Mar. 31, 2021
Current assets:
Cash and cash equivalents	$ 33,435	$ 9,500
Restricted cash	500	0
Accounts receivable, net, including $1.2 million and $507 thousand from related parties as of March 31, 2022 and March 31, 2021, respectively	2,558	1,618
Inventory	6,330	2,223
Prepaid expenses and other current assets	1,971	953
Total current assets	44,794	14,294
Property and equipment, net	1,649	1,360
Goodwill	1,180	1,302
Intangible assets, net	617	914
Investment in joint venture	143	0
Other assets	263	274
Total assets	48,646	18,144
Current liabilities:
Accounts payable and accrued expenses	3,588	3,140
Deferred revenue	346	505
Development loan	0	10,000
Revolving credit facility, including accrued interest	180	10,150
Unfunded commitment to joint venture	0	1,866
Accrued payroll and benefits	1,171	1,410
Total current liabilities	5,285	27,071
Revolving credit facility	12,000	0
Promissory note	0	16,128
Total liabilities	17,285	43,199
Commitments and contingencies (Note 10)
Stockholders’ equity (deficit):
Common stock, $0.0001 par value; 750,000,000 shares authorized as of March 31, 2022 and March 31, 2021, and 53,379,307 and 40,531,996 shares issued and outstanding as of March 31, 2022 and March 31, 2021, respectively	5	4
Additional paid-in capital	211,190	144,201
Accumulated deficit	(178,638)	(168,403)
Accumulated other comprehensive loss	(1,196)	(857)
Total stockholders’ equity (deficit)	31,361	(25,055)
Total liabilities and stockholders’ equity (deficit)	$ 48,646	$ 18,144

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2022	Mar. 31, 2021
Statement of Financial Position [Abstract]
Accounts receivable from related parties	$ 1,200	$ 507
Common stock, par value (in usd per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	750,000,000	750,000,000
Common stock, shares issued (in shares)	53,379,307	40,531,996
Common stock, shares outstanding (in shares)	53,379,307	40,531,996

Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2020
Income Statement [Abstract]
Revenue, net, including related parties (Note 16)	$ 2,425	$ 24,050	$ 11,371
Cost of goods sold	1,788	12,530	6,682
Gross profit	637	11,520	4,689
Operating expenses:
Research and development	1,780	6,655	5,584
Sales and marketing	663	3,535	2,174
General and administrative	2,733	11,226	10,328
Total operating expenses	5,176	21,416	18,086
Loss from operations	(4,539)	(9,896)	(13,397)
Interest expense	187	792	760
Loss in joint venture	1,468	3,971	6,836
Changes in fair value of promissory note	699	(605)	(927)
Other income, net	(314)	(3,819)	(2,157)
Loss before tax expense	(6,579)	(10,235)	(17,909)
Tax expense	0	0	0
Net loss	$ (6,579)	$ (10,235)	$ (17,909)
Net loss per share - basic (in usd per share)	$ (0.16)	$ (0.22)	$ (0.56)
Net loss per share - diluted (in usd per share)	$ (0.16)	$ (0.22)	$ (0.56)
Weighted average common shares outstanding - basic (in shares)	40,274,660	46,056,331	31,739,801
Weighted average common shares outstanding - diluted (in shares)	40,274,660	46,056,331	31,739,801

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2020
Statement of Comprehensive Income [Abstract]
Net loss	$ (6,579)	$ (10,235)	$ (17,909)
Other comprehensive loss, net of tax:
Foreign currency translation adjustments	(85)	(339)	(30)
Other comprehensive loss, net of tax	(85)	(339)	(30)
Comprehensive loss	$ (6,664)	$ (10,574)	$ (17,939)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

Consolidated Statements of Changes in Stockholders’ Equity (Deficit) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss
Beginning balance (in shares) at Dec. 31, 2019		4,220,998
Beginning balance at Dec. 31, 2019	$ (122,253)		$ 22,404	$ (143,915)	$ (742)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options exercised (in shares)	6,821	6,821
Stock options exercised	$ 27		27
Conversion of preferred shares in connection with the Reverse Merger (in shares)		23,933,949
Conversion of preferred shares in connection with the Reverse Merger	85,658	$ 3	85,655
Shares redeemed in connection with the Reverse Merger (in shares)		(52,773)
Shares redeemed in connection with the Reverse Merger	(211)		(211)
Shares issued in connection with the Reverse Merger (in shares)		1,650,000
Shares issued in connection with the Reverse Merger	(50)		(50)
Issuance of common stock (in shares)		10,380,000
Issuance of common stock	33,387	$ 1	33,386
Restricted stock awards issued (in shares)		139,501
Stock-based compensation	1,525		1,525
Other comprehensive loss	(30)				(30)
Net loss	(17,909)			(17,909)
Ending balance (in shares) at Dec. 31, 2020		40,278,496
Ending balance at Dec. 31, 2020	$ (19,856)	$ 4	142,736	(161,824)	(772)
Beginning balance (in shares) at Feb. 11, 2020	50,325,662
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued in connection with the Reverse Merger (in shares)	1,650,000
Ending balance (in shares) at Feb. 12, 2020	4,171,571
Beginning balance (in shares) at Dec. 31, 2020		40,278,496
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options exercised (in shares)	500	500
Stock options exercised	$ 2		2
Issuance of common stock (in shares)		250,000
Issuance of common stock	950		950
Restricted stock awards issued (in shares)		3,000
Stock-based compensation	513		513
Other comprehensive loss	(85)				(85)
Net loss	$ (6,579)			(6,579)
Ending balance (in shares) at Mar. 31, 2021	40,531,996	40,531,996
Ending balance at Mar. 31, 2021	$ (25,055)	$ 4	144,201	(168,403)	(857)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options exercised (in shares)	52,799	52,799
Stock options exercised	$ 221		221
Conversion of preferred shares in connection with the Reverse Merger (in shares)		3,120,000
Conversion of preferred shares in connection with the Reverse Merger	14,378		14,378
Issuance of common stock (in shares)		9,370,251
Issuance of common stock	50,273	$ 1	50,272
Stock-based compensation	2,614		2,614
Restricted stock units vested (in shares)		305,982
Restricted stock units surrendered due to net share settlement to satisfy employee tax liability (in shares)		(97,249)
Restricted stock units surrendered due to net share settlement to satisfy employee tax liability	(768)		(768)
Stock warrants exercised (in shares)		95,528
Stock warrants exercised	272		272
Other comprehensive loss	(339)				(339)
Net loss	$ (10,235)			(10,235)
Ending balance (in shares) at Mar. 31, 2022	53,379,307	53,379,307
Ending balance at Mar. 31, 2022	$ 31,361	$ 5	$ 211,190	$ (178,638)	$ (1,196)

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2020
Cash flows from operating activities:
Net loss	$ (6,579)	$ (10,235)	$ (17,909)
Adjustments to reconcile net loss to net cash used in operating activities:
Inventory write-off	7	196	435
Depreciation and amortization	197	843	835
Provision for doubtful accounts	(48)	0	110
Perpetual licensing revenue from a related party	0	(8,000)	(5,000)
Stock-based compensation	513	2,614	1,525
Interest cost	187	107	760
Gain on promissory note conversion	0	(1,222)	0
Gain on sale of equipment	(40)	0	0
Loss in joint venture	1,468	2,516	6,836
Changes in fair value of promissory note	699	(605)	(927)
Changes in operating assets and liabilities:
Accounts receivable	(690)	(940)	(245)
Inventory	(603)	(4,303)	(1,072)
Prepaid expenses and other current assets	108	(518)	(283)
Other assets	17	11	206
Accounts payable and accrued expenses	(195)	198	(116)
Deferred revenue	(169)	(159)	674
Accrued payroll and benefits	195	(239)	56
Net cash used in operating activities	(4,933)	(19,736)	(14,115)
Cash flows from investing activities:
Purchases of property and equipment	(164)	(595)	(58)
Investment in joint venture	(968)	(4,526)	(7,348)
Net cash used in investing activities	(1,132)	(5,121)	(7,406)
Cash flows from financing activities:
Proceeds from sale of equipment	4	0	0
Proceeds from stock option exercise	2	221	32
Proceeds from issuance of common stock	1,000	50,900	36,520
Cost associated with issuance of common stock	(50)	(1,127)	(3,133)
Proceeds from exercise of warrants	0	272	0
Payment for repurchase of common stock	0	0	(211)
Payment for taxes related to net share settlement of restricted stock units	0	(768)	0
Loan repayment	0	0	(50)
Net cash provided by financing activities	956	49,498	33,158
Effect of foreign exchange rate changes on cash, cash equivalents and restricted cash	(85)	(206)	182
Net increase (decrease) in cash, cash equivalents and restricted cash	(5,194)	24,435	11,819
Cash, cash equivalents and restricted cash at beginning of period	14,694	9,500	2,875
Cash, cash equivalents and restricted cash at end of period	9,500	33,935	14,694
Supplemental disclosures of cash flow information:
Interest expense paid	153	685	915
Supplemental non-cash investing activity:
Equipment purchases	0	250	0
Supplemental non-cash financing activity:
Issuance of shares in connection with a service contract	0	500	0
Development loan reduction related to perpetual licensing revenue	0	8,000	5,000
Conversion of promissory note	0	15,600	0
Conversion of preferred stock to common stock in connection with the Reverse Merger	0	0	85,658
Private placement offering cost	$ 0	$ 0	$ 223

Consolidated Statements of Changes in Stockholders’ Equity (Deficit) (Parenthetical) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($)
Statement of Stockholders' Equity [Abstract]
Stock issuance costs	$ 3,133
Warrant costs	$ 223

Business and Basis of Presentation	12 Months Ended
Business and Basis of Presentation	Mar. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business and Basis of Presentation	Business and Basis of Presentation Transphorm, Inc. (“Parent”) develops gallium nitride (“GaN”) semiconductor components used in power conversion and is headquartered in Goleta, California. Parent’s wholly owned-subsidiary, Transphorm Technology, Inc. (“Transphorm Technology”), was incorporated in the State of Delaware on February 22, 2007. Throughout these notes, “the Company,” “Transphorm,” “we,” “us” and “our” refer to Parent and its direct and indirect wholly-owned subsidiaries. Transphorm Technology and its subsidiaries hold all material assets and conduct all business activities and operations of the Company. Transphorm Technology’s activities to date have been primarily performing research and development, establishing manufacturing infrastructure, market sampling, product launch, hiring personnel, and raising capital to support and expand these activities. Transphorm Japan, Inc. was established in Japan in February 2014 to secure Transphorm’s production capacity and establish a direct presence in Asian markets. Transphorm Aizu, Inc. was established in Japan to manage the financial transactions around Aizu Fujitsu Semiconductor Wafer Solution Limited, Transphorm’s non-controlling joint venture wafer fabrication facility located in Aizu Wakamatsu, Japan (“Aizu”). Transphorm Japan Epi, Inc. was established in Japan in 2019 to enable the operational capacity of the reactors held in Aizu. Change in Fiscal Year End On April 20, 2021, we changed our fiscal year from the period beginning on January 1 and ending on December 31 to the period beginning on April 1 and ending on March 31 of each year, effective immediately. Accordingly, we filed a Transition Report on Form 10-K on June 24, 2021 to include audited consolidated financial information for the transition period from January 1, 2021 through March 31, 2021. Reverse Merger On February 12, 2020, our wholly-owned subsidiary, Peninsula Acquisition Sub, Inc., a corporation formed in the State of Delaware (“Acquisition Sub”), merged with and into Transphorm Technology (formerly known as Transphorm, Inc.), the corporate existence of Acquisition Sub ceased, and Transphorm Technology became our wholly-owned subsidiary (such transaction, the “Merger”). As a result of the Merger, we acquired the business of Transphorm Technology. The Merger was effective as of February 12, 2020, upon the filing of a certificate of merger with the Secretary of State of the State of Delaware. Immediately after completion of the Merger, we adopted Transphorm Technology’s former company name, “Transphorm, Inc.”, as our company name. The Merger was treated as a recapitalization and reverse acquisition for financial reporting purposes, and Transphorm Technology is considered the acquirer for accounting purposes. As a result of the Merger and the change in our business and operations, a discussion of the past financial results of our predecessor, Peninsula Acquisition Corporation, is not pertinent, and under applicable accounting principles, the historical financial results of Transphorm Technology, the accounting acquirer, prior to the Merger are considered our historical financial results. At the effective time of the Merger, (i) each share of Transphorm Technology’s common stock issued and outstanding immediately prior to the closing of the Merger was converted into the right to receive (a) 0.08289152527 shares of our common stock (in the case of shares held by accredited investors) or (b) $4.00 multiplied by 0.08289152527 (in the case of shares held by unaccredited investors), with the actual number of shares of our common stock issued to the former holders of Transphorm Technology’s common stock equal to 4,171,571, (ii) 51,680,254 shares of Transphorm Technology’s Series 1 preferred stock issued and outstanding immediately prior to the closing of the Merger were converted into 12,433,953 shares of our common stock, (iii) 38,760,190 shares of Transphorm Technology’s Series 2 preferred stock issued and outstanding immediately prior to the closing of the Merger were converted into 7,499,996 shares of our common stock, and (iv) 31,850,304 shares of Transphorm Technology’s Series 3 preferred stock issued and outstanding immediately prior to the closing of the Merger were converted into 4,000,000 shares of our common stock. As a result, 28,105,520 shares of our common stock were issued to the former holders of Transphorm Technology’s issued and outstanding capital stock after adjustments due to rounding for fractional shares. Immediately prior to the effective time of the Merger, an aggregate of 682,699 shares of our common stock, owned by the stockholders of Peninsula Acquisition Corporation prior to the Merger, were forfeited and cancelled. In addition, pursuant to the Merger Agreement, (i) options to purchase 29,703,285 shares of Transphorm Technology’s common stock issued and outstanding immediately prior to the closing of the Merger under Transphorm Technology’s 2007 Stock Plan (the “2007 Plan”) and 2015 Equity Incentive Plan (the “2015 Plan”) were assumed and converted into options to purchase 2,461,923 shares of our common stock, (ii) warrants to purchase 186,535 shares of Transphorm Technology’s common stock issued and outstanding immediately prior to the closing of the Merger were assumed, amended and converted into warrants to purchase 15,461 shares of our common stock, and (iii) Transphorm Technology’s outstanding convertible promissory note was amended to be convertible at the option of the holder, into shares of our common stock at a conversion price of $5.12 per share. On October 4, 2021, the promissory note of $15.6 million, consisting of an outstanding principal amount of $15.0 million plus accrued but unpaid interest of $600 thousand, was further amended to reduce the conversion price from $5.12 per share to $5.00 per share and converted into an aggregate of 3,120,000 shares of our common stock. See Note 13 - Fair Value Measurements, Note 9 - Debts and Note 11 - Stockholders’ Equity (Deficit). All per share and share amounts for all periods presented have been retroactively adjusted to reflect the effect of the Merger. Liquidity and Capital Resources The Company’s ability to sustain operations is dependent mainly on its ability to successfully market and sell its products and its ability to raise capital through additional financings until it is able to achieve profitability with positive cash flows. The Company currently incurs and historically has incurred losses from operations and expects to do so in the foreseeable future. During the year ended March 31, 2022, the Company used $19.7 million of cash in operations. Although the Company expects to continue to incur losses and sustain negative cash flows from operating activities, during the year ended March 31, 2022, the Company raised gross proceeds of $50.9 million from private placements. Consequently, the Company has sufficient resources to fund its operations for the next twelve months from the date of this filing. The Company may need to continue to raise additional capital to finance its losses and negative cash flows from operations beyond the next twelve months and may continue to be dependent on additional capital raises. Impact of COVID-19 on Our Business The COVID-19 pandemic has adversely disrupted and will further disrupt the operations at certain of our customers, partners, suppliers and other third-party providers for an uncertain period of time, including as a result of travel restrictions, adverse effects on budget planning processes, business deterioration, and/or business shutdowns, all of which has impacted our business and results of operations. Some of our customers have experienced delays in their internal development programs and design cycles with our GaN products due to the effects of COVID-19, which have led to postponements of their orders of our products and postponements of determinations that our products will be used in their designs for new products under development with corresponding delays in their market introduction and our revenues. While the impact of COVID-19 on our business and results of operations has not been significant to date, and we do not expect to see any significant impact in the near term, any future impact of COVID-19 cannot be predicted with certainty and may make it more difficult or preclude us from raising additional capital, increase our costs of capital and otherwise adversely affect our business, results of operations, financial condition and liquidity.

Summary of Significant Accounting Policies	12 Months Ended
Summary of Significant Accounting Policies	Mar. 31, 2022
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting PoliciesPrinciples of Consolidation The consolidated financial statements include the accounts of the Parent and its wholly-owned subsidiaries, Transphorm Technology, Transphorm Japan, Inc., Transphorm Japan Epi, Inc. and Transphorm Aizu, Inc. Upon consolidation, all significant intercompany accounts and transactions have been eliminated. Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Management bases its estimates and assumptions on historical experience, knowledge of current conditions, and its belief of what could occur in the future, given available information. Actual results could differ from those estimates, and such differences could be material to the consolidated financial statements. Estimates are used for, but not limited to, the determinations of fair value of stock awards and promissory notes, accrual of expenses, revenue recognition, allowance for doubtful accounts, inventory reserve, and useful lives for property and equipment. Cash, Cash Equivalents and Restricted Cash The Company considers all highly-liquid investments with original maturities of 90 days or less at the date of purchase to be cash equivalents. Cash and cash equivalents consist principally of bank deposits and money market funds. Restricted cash of $575 thousand as of March 31, 2022 consists of $500 thousand of cash in current asset and $75 thousand of long-term deposit in other assets. Restricted cash of $75 thousand as of March 31, 2022 and 2021 consists of long-term deposit in other assets. Foreign Currency Risk The Company is exposed to foreign currency risk due to its operations in Japan (Yen). Assets and liabilities of the operations are re-measured into U.S. currency at exchange rates in effect at the balance sheet dates through the consolidated statements of comprehensive income. Gains or losses resulting from foreign currency transactions are re-measured using the rates on the dates on which those elements are recognized during the period and are included in other income or expense in the consolidated statements of operations. Changes in the value of our cash balance due to fluctuations in foreign exchange rate are presented on the consolidated statements of cash flows as effect of foreign exchange rate changes on cash, cash equivalents and restricted cash. As of March 31, 2022 and March 31, 2021, the Company had foreign cash and cash equivalents of $66 thousand and $444 thousand, respectively, which represented 0.2 percent and 4.7 percent, respectively, of total cash and cash equivalents. Concentrations of Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash and cash equivalents. The Company is exposed to credit risk in the event of default by the financial institution holding its cash. The Company’s investment policy restricts investments to high-quality investments and limits the amounts invested with any one issuer, industry or geographic area. Risks associated with cash holdings in excess of insured limits are mitigated by banking with high-quality institutions. To date, the Company has not experienced any significant losses on its cash and cash equivalents. The Company periodically evaluates the relative credit standing of these financial institutions. The Company is subject to risks common in the power conversion components industry, including, but not limited to, technological obsolescence, dependence on key personnel, market acceptance of its products, the successful protection of its proprietary technologies, compliance with government regulations, and the possibility of not being able to obtain additional financing when needed. Comprehensive Loss Comprehensive loss is comprised of net loss and other comprehensive loss. Other comprehensive loss includes the impact of foreign currency translation adjustments. Accounts Receivable Accounts receivable are analyzed and allowances for uncollectible accounts are recorded, as required. Provisions for uncollectible accounts, if any, are recorded as bad debt expense and included in general and administrative expenses in the accompanying consolidated statements of operations. The process for determining the appropriate level of allowances for doubtful accounts involves judgment, and the Company considers such factors as the age of the underlying receivables, historical and projected collection trends, the composition of outstanding receivables, current economic conditions and regulatory changes. An account is fully reserved when reasonable collection efforts have been unsuccessful and it is probable that the receivable will not be recovered. No provision for doubtful accounts was recorded for the year ended March 31, 2022 as substantially all of the accounts receivables were collected subsequently. Recovery from doubtful accounts amounted to $48 thousand for the three months ended March 31, 2021. Provision for doubtful accounts amounted to $110 thousand for the year ended December 31, 2020. Inventory Inventory is stated at the lower of cost (first-in, first-out method) or net realizable value. The Company periodically reviews the value of items in inventory and records write-downs or write-offs based on its assessment of slow moving or obsolete inventory. The Company maintains an inventory reserve for obsolete inventory and generally makes inventory value adjustments against the inventory reserve. Property and Equipment Property and equipment are stated at cost, net of accumulated depreciation and amortization. Depreciation is determined using the straight-line method over the estimated useful lives of the respective assets, generally ranging from three to seven years. Leasehold improvements are amortized on a straight-line basis over the shorter of their estimated useful lives or the related lease term. Depreciation for equipment commences once it is placed in service, and depreciation for buildings and leasehold improvements commences once they are ready for their intended use. The Company expenses maintenance and repair costs that do not extend the life of the asset as they are incurred. The Company evaluates the carrying amount of its property and equipment whenever events or changes in circumstances indicate that the assets may not be recoverable. An impairment loss would be recognized when estimated future cash flows expected to result from the use of an asset or asset group and its eventual disposition are less than the carrying amount of the asset or asset group. To date, there have been no such impairment losses. Goodwill Goodwill arose for the acquisition of a business in February 2014 based in Japan and was accounted for as the purchase of a business. Goodwill generated from business combinations and deemed to have indefinite lives are not subject to amortization and instead are tested for impairment at least annually in December unless certain events occur or circumstances change. Goodwill represents the excess of the purchase price over the fair value of the net assets and other identifiable intangible assets acquired. We test for goodwill impairment annually, on March 31, or earlier if events or changes in circumstances indicate goodwill might possibly be impaired. Impairment exists when the carrying value of the goodwill exceeds its implied fair value. An impairment loss would be recognized in an amount equal to that excess as a charge to operations in the consolidated statements of operations. For the year ended March 31, 2022, the three months ended March 31, 2021, and the year ended December 31, 2020, no impairment charge was recorded related to goodwill. Intangible Assets Intangible assets that are not considered to have an indefinite useful life are amortized over their estimated useful lives, which generally range from three to ten years. Each reporting period, the Company evaluates the estimated remaining useful lives of intangible assets and whether events or changes in circumstances warrant a revision to the remaining periods of amortization. If it is determined that the carrying values might not be recoverable based upon the existence of one or more indicators of impairment, the Company performs a test for recoverability using various methodologies, such as the income approach or cost approach, to determine the fair value of intangible assets depending upon the nature of the assets. If assets are considered to be impaired, the impairment to be recognized is measured as the amount by which the carrying amount of the assets exceeds their respective fair values. For the year ended March 31, 2022, the three months ended March 31, 2021 and the year ended December 31, 2020, no impairment charges were recorded related to intangible assets. Revenue Recognition The Company derives its revenues from sales of high-powered GaN-based products manufactured utilizing the Company’s proprietary and patented epiwafer technology and wafer fabrication and other assembly processes, sales of GaN epiwafers for the radio frequency (“RF”) and power markets, and sales of licenses to use such patented proprietary technology, as well as enabling EPI wafer growth services and products to our strategic partners. Revenues are recognized when control of these products or licenses are transferred to the Company’s customers in an amount that reflects the consideration it expects to be entitled to in exchange for those products and licenses. Sales and other taxes the Company collects concurrent with revenue-producing activities are excluded from revenue. Incidental items that are immaterial in the context of the contract are recognized as expense. The Company does not have any significant financing components associated with its revenue contracts, as payment is received at or shortly after the point of sale. Disaggregation of Revenue from Contracts with Customers Revenue consists of perpetual licensing revenue, government contract revenue from our contract with the U.S. Navy and product sales, with applicable performance obligations satisfied at a point in time. Products are sold to distributors and end-users in various sectors such as, but not limited to, the automotive, gaming, industrial, IT, and consumer products industries. As part of the multi-element commercial arrangement executed with Nexperia on April 4, 2018 (see Note 3 - Nexperia Arrangement), the Company agreed to grant Nexperia the perpetual exclusive right to use the Company’s existing Gen-3 manufacturing process technology. License fees are received upon satisfaction of contractual milestones and recognized upon delivery of the perpetual license or transferred technology without any remaining performance obligations. The Company recognized $8.0 million of perpetual licensing revenue for the year ended March 31, 2022. No perpetual licensing revenue was recognized for the three months ended March 31, 2021. The Company recognized $5.0 million of perpetual licensing revenue for the year ended December 31, 2020. In December 2020, the Company entered into a cooperation and development agreement with Yaskawa Electric Corporation (“Yaskawa”), pursuant to which Yaskawa agreed to provide $4.0 million over approximately three years to fund development activities related to industrial power conversion applications, with an initial focus on servo motor drive applications. Yaskawa provided payments of $1.0 million and $750 thousand of this $4.0 million commitment in December 2020 and July 2021, respectively. The Company evaluated and concluded that the deliverables are the same and nature of the services to be provided to Yaskawa will be consistent over the period of approximately three years. Accordingly, with respect to the $1.8 million payment, the Company recognized $1.1 million as revenue for the year ended March 31, 2022, $333 thousand as revenue for the three months ended March 31, 2021 and $333 thousand as revenue for the year ended December 31, 2020. The Company also recorded $375 thousand as revenue for services rendered but not billed for the year ended March 31, 2022. Government contract revenues are principally generated under research and development contracts. Contract revenues are derived primarily from research contracts with agencies of the U.S. government. We believe credit risk related to accounts receivable arising from such contracts is minimal. These contracts may include cost-plus fixed fee and fixed price terms. All payments to us for work performed on contracts with agencies of the U.S. government are subject to adjustment upon audit by the Defense Contract Audit Agency. The contract’s expiration dates were initially March and June 2022, but such dates were subsequently extended to June and December 2022, respectively. The Company received new government authorized rates for billing purposes which allowed for retroactive application since inception. The cumulative impact of this rate change as of March 31, 2022 was $423 thousand, of which $(83) thousand and $505 thousand were recorded in the three months ended March 31, 2021 and year ended December 31, 2021, respectively. On February 1, 2022, the Company received new government authorized rates which allowed for retroactive application effective for the year ended December 31, 2020. The Company will use the new approved rates on a go-forward basis. Performance Obligations For performance obligations related to the sale of products, control transfers to the customer at a point in time. The Company’s principal terms of sale are free on board shipping or destination and the Company transfers control and records revenue for product sales upon shipment or delivery to the customer, respectively. For performance obligations related to the licensing of patented technology in perpetuity, control also transfers to the customer at a point in time. The Company transfers control and records revenue for licensing fees once the Company has (i) provided or otherwise makes available the patented technology to the customer and (ii) the customer is able to use and benefit from the patented technology. Variable Consideration The nature of the Company’s arrangement with Nexperia gives rise to variable consideration in the form of milestone and royalty payments. The royalties qualify for the sales and usage-based royalty exception, as the license of intellectual property is the predominant item to which the royalty relates and are recognized upon the subsequent sale occurring. The variable amounts are received upon satisfaction of contractually agreed upon development targets and sales volume. Research and Development The Company is a party to research grant contracts with the U.S. government for which the Company is reimbursed for specified costs incurred for its research projects. These projects include energy saving initiatives for which the U.S. government offers reimbursement funds. Such reimbursements are recorded as an offset to research and development expenses when the related qualified research and development expenses are incurred. Reimbursable costs are recognized in the same period the costs are incurred up to the limit of approved funding amounts on qualified expenses. Grant reimbursement of $345 thousand, $42 thousand and $426 thousand was recorded as an offset to research and development expense for the year ended March 31, 2022, the three months ended March 31, 2021 and the year ended December 31, 2020. Stock-Based Compensation All share-based payments, including grants of stock options, restricted stock awards (“RSAs”) and restricted stock units (“RSUs”), are measured at the fair value of the share-based awards on the grant date and recognized over their respective vesting periods, which is generally one to four years. The estimated fair value of stock options at the grant date is determined using the Black-Scholes-Merton pricing model, and the RSAs and RSUs are measured using the fair market value of the stock price at grant date. The Company recognizes the fair value of share-based payments as compensation expense for all expected-to-vest stock-based awards over the vesting period of the award using the straight-line attribution or graded vesting method provided that the amount of compensation cost recognized at any date is no less than the portion of the grant-date fair value of the award that is vested at that date. The Black-Scholes-Merton option pricing model requires inputs such as the fair value of common stock on date of grant, expected term, expected volatility, dividend yield, and risk-free interest rate. Further, the forfeiture rate also affects the amount of aggregate compensation expense. These inputs are subjective and generally require significant analysis and judgment to develop. Volatility data is obtained from a study of publicly traded industry peer companies. The forfeiture rate is derived primarily from the Company’s historical data, and the risk-free interest rate is based on the yield available on U.S. Treasury zero-coupon issues commensurate with the expected term. Management generally uses the simplified method to calculate the expected term for employee grants as the Company has limited historical exercise data or alternative information to reasonably estimate an expected term assumption. The simplified method assumes that all options will be exercised midway between the weighted average vesting date and the contractual term of the option. Stock-based compensation expense recognized in the Company’s consolidated financial statements is based on awards that are expected to vest. These expense amounts have been reduced by using an estimated forfeiture rate. Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. The Company evaluates the assumptions used to estimate forfeitures annually in connection with the recognition of stock-based compensation expense. Income (Loss) Per Share Basic income (loss) per share is calculated by dividing net income (loss) applicable to common stockholders by the weighted average number of common shares outstanding during the period. Diluted income (loss) per share is calculated by dividing the net loss attributable to common stockholders by the sum of the weighted average number of common shares outstanding plus potential dilutive common shares outstanding during the period. Potential dilutive securities, comprised of stock warrants, restricted stock units and stock options, are not reflected in diluted income (loss) per share because such shares are anti–dilutive. Dilutive impact of potential common shares resulting from common stock equivalents is determined by applying the treasury stock method. For the year ended March 31, 2022, there were 6,491,081 shares, consisting of 2,879,008 stock options, 954,775 restricted stock units and 2,657,298 stock warrants, that were not included in the computation of diluted loss per share because their effect would be anti-dilutive. For the three months ended March 31, 2021, there were 3,637,937 shares, consisting of 2,543,125 stock options, 935,397 restricted stock units and 159,415 stock warrants, that were not included in the computation of diluted loss per share because their effect would be anti-dilutive. For the year ended December 31, 2020, there were 3,285,058 shares, consisting of 2,320,318 stock options, 805,325 restricted stock units and 159,415 stock warrants, that were not included in the computation of diluted loss per share because their effect would be anti-dilutive. Fair Value Measurement Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The carrying values of the Company’s financial instruments such as cash equivalents, accounts receivable, revolving credit facility, accounts payable and accrued liabilities approximate fair values due to the short-term nature of these items. Income Taxes The Company accounts for income taxes in accordance with Accounting Standards Codification (“ASC”) 740, Income Taxes (“ASC 740”). ASC 740 prescribes the use of the liability method. Deferred tax assets and liabilities are determined based on the difference between the financial statement carrying amounts and the tax basis of assets and liabilities and are measured using the enacted statutory tax rates in effect at the balance sheet date. The Company records a valuation allowance to reduce its deferred tax assets when uncertainty regarding their realizability exists. Equity Method Investments The Company uses the equity method to account for investments in entities that it does not control, but in which it has the ability to exercise significant influence over operating and financial policies. The Company's proportionate share of the net income or loss of these companies is included in consolidated net loss. Judgments regarding the level of influence over each equity method investment include consideration of key factors such as the Company's ownership interest, representation on the board of directors or other management body and participation in policy-making decisions. Segment Reporting The Company’s operations and its financial performance is evaluated on a consolidated basis by the chief operating decision maker. The Company’s chief operating decision maker is the Parent’s Chief Executive Officer. Accordingly, the Company considers all of its operations to be aggregated in one reportable operating segment. For the year ended March 31, 2022, total revenue was $24.1 million, of which $23.4 million was from U.S. operations and $698 thousand was from Japan operations. For the three months ended March 31, 2021, total revenue was $2.4 million, of which $2.0 million was from U.S. operations and $449 thousand was from Japan operations. For the year ended December 31, 2020, total revenue was $11.4 million, of which $10.7 million was from U.S. operations and $713 thousand was from Japan operations. Recently Issued Accounting Standards under Evaluation Debt - In August 2020, the FASB issued ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity, to address the complexity in accounting for certain financial instruments with characteristics of liabilities and equity. Amongst other provisions, the amendments in this ASU significantly change the guidance on the issuer’s accounting for convertible instruments and the guidance on the derivative scope exception for contracts in an entity’s own equity such that fewer conversion features will require separate recognition, and fewer freestanding instruments, like warrants, will require liability treatment. Refer to our white paper, Accounting simplifications for convertible instruments and warrants, for additional information. ASU 2020-06 is effective for fiscal years beginning after December 15, 2021. The Company is currently evaluating the impact of this new standard on its consolidated financial statements and the adoption is not expected to have a significant impact on the consolidated financial statements. Leases - In June 2020, the FASB issued ASU 2020-05, which amends the effective dates of the FASB’s standards on leasing (ASC 842) to give immediate relief to certain entities as a result of the widespread adverse economic effects and business disruptions caused by the COVID-19 pandemic. In February 2016, the FASB issued ASU 2016-02, Leases, which, for operating leases, requires the lessee to recognize a right-of-use asset and a lease liability, initially measured at the present value of the lease payments, on its balance sheet. The guidance also requires a lessee to recognize single lease costs, calculated so that the cost of the lease is allocated over the lease term, on a generally straight-line basis. The leasing standard’s effective dates were the fiscal year beginning after December 15, 2019 as originally issued (ASU 2016-02) and the fiscal year beginning after December 15, 2020 as amended by ASU 2019-10. As amended by ASU 2020-05, the leasing standard’s effective date is now the fiscal year beginning after December 15, 2021. The Company is currently evaluating the impact of this new standard on its consolidated financial statements and the adoption is not expected to have a significant impact on the consolidated financial statements. Financial Instruments - FASB ASU 2020-03, Codification Improvements to Financial Instruments, makes clear the determination of the contractual life of a net investment in leases in estimating expected credit losses under ASC 326, Financial Instruments – Credit Losses. In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”). The standard changes the methodology for measuring credit losses on financial instruments and the timing of when such losses are recorded. ASU 2016-13 is effective for the Company in 2023. Early adoption is permitted. The Company is currently evaluating the impact of this new standard on its consolidated financial statements and the adoption is not expected to have a significant impact on the consolidated financial statements. Income Tax - In December 2019, the FASB issued ASU 2019-12, which modifies ASC 740 to simplify the accounting for income taxes. The ASU’s amendments are based on changes that were suggested by stakeholders as part of the FASB’s simplification initiative (i.e., the FASB’s effort to reduce the complexity of accounting standards while maintaining or enhancing the helpfulness of information provided to financial statement users). ASU 2019-12 is effective for fiscal years beginning after December 15, 2022. The Company is currently evaluating the impact of this new standard on its consolidated financial statements and the adoption is not expected to have a significant impact on the consolidated financial statements.

Nexperia Arrangement	12 Months Ended
Nexperia Arrangement	Mar. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nexperia Arrangement	Nexperia Arrangement Nexperia Transaction On April 4, 2018, the Company entered into a multi-element commercial arrangement with Nexperia B.V. (“Nexperia”) to obtain financing in exchange for the sale of equity instruments and performing certain technology and product development activities for Nexperia (collectively, the “Collaboration Arrangement”). Nexperia specializes in designing, manufacturing and selling a broad range of small discrete semiconductor devices that utilize components such as those manufactured by the Company. Financing under the Collaboration Arrangement is comprised of the following elements: •$16 million Series 3 preferred stock issuance •$9 million license fee for transfer of the Gen-3 manufacturing process •$5 million development loan, originally maturing March 31, 2020 and subsequently extended to June 30, 2020 intended to pre-fund the Gen-4 (Tranche A) technology development (the “Tranche A Loan”) •$10 million development loan maturing March 31, 2021 intended to pre-fund the Gen-5 and 900V technology development (the “Tranche B Loan”) •$10 million revolving loan (the “Tranche C Loan”) By entering into this Collaboration Arrangement, Nexperia gained access to technology that allows for the production of high power semiconductors for use in electric vehicles. Further, Nexperia obtained an exclusive license and market access to automotive customers outside of Japan and a sole license (non-exclusive of the Company), as well as market access to customers in other parts of the power market. Nexperia has a lien on certain of the Company’s U.S. patents not relating to metal organic chemical vapor deposition (“MOCVD”) or epiwafer technology, per the agreement. On March 31, 2019, the Company executed Amendment No. 1 to the Loan and Security Agreement (the ”LSA”), pursuant to which the Tranche B Loan was bifurcated into the following two separate sub-tranches: •$8 million development loan intended to pre-fund the Gen-5 and 900V (Tranche B) technology development (the “Tranche B Loan”) •$2 million development loan intended to pre-fund the 1200V technology development (the “Tranche B-1 Loan” and, together with the Tranche B Loan, the “Tranche B Loans”) On February 7, 2020, Amendment No. 2 to the LSA was executed to acknowledge the then-pending Merger, reaffirm the terms of the loans and confirm the waiver for the late delivery of the Company’s 2018 audited financial statements. On April 8, 2020, Amendment No. 3 to the LSA was executed to extend the maturity of the Tranche A Loan to April 30, 2020. On April 28, 2020, Amendment No. 4 to the LSA was executed to further extend the maturity of the Tranche A Loan to June 30, 2020. All other terms set forth under the original LSA remained unchanged following the amendments. The Tranche A and Tranche B Loans represent pre-funding for Gen-4 (Tranche A), Gen-5 (Tranche B), and 900V (Tranche B-1) technology development for Nexperia. The specific development activities and associated performance milestones are contained within a Statement of Work (“SoW”) between the Company and Nexperia. The SoW may be modified from time to time based upon mutual business interests. This promise to perform the technology development is a good/service provided to a customer in exchange for consideration in the form of the technology development license fees that offset the Tranche A and Tranche B Loans outstanding. The Development Loans are recognized as a liability equal to the cash proceeds received. In relation to the license fee for the transfer of the Company’s Gen-3 manufacturing process to Nexperia, the Company received $3 million (the first of three tranches) in October 2018, $3 million (the second of three tranches) in April 2019, and $3 million (the third of three tranches) in October 2019. The Company recognized $9.0 million as perpetual licensing revenue during 2019 upon the completion of the transfer of the Company’s Gen-3 manufacturing process technology and mutual sign off between Nexperia and the Company. In January 2019, the Company received the $5 million Tranche A Loan. In June 2020, Nexperia agreed that the $5 million Tranche A Loan was permanently satisfied in full in connection with the Company transferring its Gen-4 technology development to Nexperia, at which point the Company recognized $5 million as perpetual licensing revenue. In June and July 2019, the Company received the $8 million Tranche B Loan. In December 2019, the Company received the $2 million Tranche B-1 Loan. The Company received the full $10 million Tranche C Loan under the credit facility during the year ended December 31, 2018. See Note 9 - Debts. On March 1, 2021, Amendment No. 5 to the LSA was executed to extend the maturity of the Tranche B loans of $10 million and the Tranche C Loan of $10 million to June 30, 2021 and May 18, 2021, respectively. On May 18, 2021, Amendment No. 6 to the LSA was executed to (1) extend the maturity date for the Tranche C Loans to the earlier of April 4, 2023 and the occurrence of specified change of control events, (2) add Parent as a guarantor of Transphorm Technology’s obligations under the Loan Agreement, and (3) convert the outstanding $2 million Tranche B-1 Loan into a Tranche C-1 Loan, which Tranche C-1 Loan has the same terms and conditions as the existing Tranche C Loan. On May 18, 2021, in addition to Amendment No. 6 to the LSA, the Company entered into a series of agreements with Nexperia, as described below. Strategic Cooperation Agreement The strategic cooperation agreement serves as a framework agreement that describes the numerous agreements between the parties and provides Nexperia with information rights and inspection rights with respect to the Company’s business. Option Agreement The option agreement establishes the parameters pursuant to which Nexperia, in certain limited instances, is permitted to exercise an option (the “Option”) to acquire Transphorm Japan Epi, Inc. (“TJE”), a Japanese subsidiary of the Company through which the Company is engaged in the development, manufacturing and sales of gallium nitride (“GaN”) based epitaxial wafer products. In general, the Option is exercisable upon (1) certain acquisitions of securities or assets of the Company or its subsidiaries by a Competitor (as defined in the option agreement) that results in the Company, directly or indirectly, owning less than a majority of TJE, which acquisition is followed by any material breach (that is not cured within a specified time period) by the Company or a subsidiary of its obligations with respect to epiwafer supply to Nexperia under the Company’s amended and restated supply agreement (the “Supply Agreement”) with Nexperia, or (2) the unilateral termination by the Company of the Supply Agreement. The option agreement also establishes the material terms, including price and timing, for the exercise of the Option by Nexperia. The Option terminates (1) if the Option is not exercised by Nexperia prior to the date on which the option agreement terminates, or (2) on the first to occur of (a) the termination of the option agreement upon written agreement of the parties, (b) the mutual termination or expiration of the Supply Agreement, or (c) the first to occur of (i) two years following the date on which the Company notifies Nexperia of epiwafer qualification of a second source and (ii) April 1, 2028. In connection with the option agreement, the Company has also amended and restated its existing intracompany license agreement with TJE to clarify Nexperia’s rights upon exercise of the Option. Amended and Restated Development and License Agreement The Company entered into an amended and restated development and license agreement (the “DLA”) with Nexperia, pursuant to which the Company agreed to develop and transfer to Nexperia certain manufacturing process technologies to enable Nexperia to manufacture GaN-based products at Nexperia’s facilities. These technologies to be transferred included the Company’s Gen-3, Gen-4 (Tranche A), and Gen-5 and 900V (Tranche B) process technologies, but do not include the Company’s Epi Process Technology (as defined in the DLA). Nexperia also agreed to provide funding for the development of such technologies in return for limited exclusivities in automotive and other fields. Nexperia’s rights now include sale of products in the automotive field in Japan along with Transphorm’s rights for sale of products in the automotive field in Japan which remain in place. As per the original agreement, after April 2023, Nexperia’s exclusive rights for sale of products in the automotive field outside of Japan terminate. In addition, the parties have clarified the ability of Nexperia’s customers to use products developed by Nexperia through exercise of its rights under this agreement. Amended and Restated Supply Agreement The Company entered into the Supply Agreement with Nexperia, which sets forth the terms under which Nexperia may purchase epiwafers and processed wafers from the Company, and the Company may purchase processed wafers from Nexperia. The agreement specifies that Nexperia is the Company’s priority customer with respect to epiwafers manufactured by TJE and, accordingly, has preferred utilization of extra capacity, and further specifies procedures to address expansion of the Company’s epiwafer manufacturing capacity and Nexperia’s obligations with respect thereto. The term of the Supply Agreement was extended until December 31, 2025, with automatic one year renewals thereafter, and the Company may not terminate the Supply Agreement while the Option Agreement is in effect. On June 30, 2021, Amendment No. 7 to the LSA was executed to extend the maturity of the Tranche B loans of $8 million to July 16, 2021. On July 16, 2021, Nexperia agreed that the $8 million Tranche B Loan was satisfied in full in connection with the Company transferring its Gen-5 and 900V technology developments to Nexperia, at which point the Company recognized $8 million as perpetual licensing revenue.

Concentration of Credit Risk and Significant Customers

12 Months Ended

Mar. 31, 2022

Risks and Uncertainties [Abstract]

Concentration of Credit Risk and Significant Customers

The Company manages its credit risk associated with exposure to distributors and direct customers on outstanding accounts receivable through the application of credit approvals and other monitoring procedures. Credit sales, which are mainly on credit terms of 30 to 60 days, are only made to customers who meet the Company's credit standards, while sales to new customers or customers with low credit ratings are usually made on an advance payment basis. The Company closely monitors the aging of accounts receivable from its distributors and direct customers, and regularly reviews their financial positions, where available.

Significant customers are those that represent 10% or more of revenue or accounts receivable.

Total revenues, by percentage, from individual customers representing 10% or more of total revenues in the respective periods were as follows:

For the Year Ended March 31, 2022

For the Three Month Transition Period Ended March 31, 2021

For the Year Ended December 31, 2020

Customer A

42.4%

27.3%

59.6%

Customer B

16.1%

31.2%

29.2%

Customer C

19.6%

Customer D

* Less than 10% of total

Accounts receivable, by percentage, from individual customers representing 10% or more of accounts receivable are set forth in the following table:


	As of March 31,
	2022	2021
Customer A	20.1%	31.1%
Customer B	19.4%	33.9%
Customer C	38.8%	*
Customer D	*	10.0%

* Less than 10% of total

Customer A is a related party and Customer B is a government agency. JCP Capital Management, LLC Limited is a majority stockholder of Customer C. See Note 8 - Investment in Joint Venture and Note 16 - Related Party Transactions.

Inventory

12 Months Ended

Mar. 31, 2022

Inventory Disclosure [Abstract]

Inventory

Inventory consists of the following as of the dates presented (in thousands):


	March 31, 2022		March 31, 2021
Raw materials	$	2,412	$	626
Work in process	1,865		1,054
Finished goods	2,053		543
Total	$	6,330	$	2,223

The Company recorded inventory write-off of $196 thousand for the year ended March 31, 2022, $7 thousand for the three months ended March 31, 2021 and $435 thousand for the year ended December 31, 2020.

Property and Equipment

12 Months Ended

Mar. 31, 2022

Property, Plant and Equipment [Abstract]

Property and Equipment

Property and equipment as of the dates presented consists of the following (in thousands except years):


	March 31, 2022		March 31, 2021		Estimated Useful Life (in years)
Machinery and equipment	$	15,255	$	14,748	5
Computer equipment and software	872		836		3
Furniture and fixtures	179		185		7
Leasehold improvements (1)	4,950		4,959		7
Construction in progress	384		137
Property and equipment, gross	21,640		20,865
Less: accumulated depreciation and amortization	(19,991)		(19,505)
Property and equipment, net	$	1,649	$	1,360

(1) Leasehold improvements are amortized on a straight-line basis over the shorter of their estimated useful lives or the related remaining lease term.

The Company recorded depreciation and amortization expense related to property and equipment of $546 thousand for the year ended March 31, 2022, $123 thousand for the three months ended March 31, 2021 and $509 thousand for the year ended December 31, 2020.

The Company recognized $40 thousand as gain on sale of equipment in general and administrative expense for the three months ended March 31, 2021.

Intangible Assets

12 Months Ended

Mar. 31, 2022

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible Assets

The carrying values of intangible assets as of the dates presented, respectively, consists of the following (in thousands except years):


	March 31, 2022
	Gross		Accumulated Amortization		Foreign Exchange Rate Changes		Net		Estimated Useful Life (in years)
Patents	$	2,963	$	(2,346)	$	—	$	617	10
Developed technology - 150V	560		(517)		(43)		—		6
Developed technology - 600V	1,701		(1,570)		(131)		—		6
Total	$	5,224	$	(4,433)	$	(174)	$	617

	March 31, 2021
	Gross		Accumulated Amortization		Foreign Exchange Rate Changes		Net		Estimated Useful Life (in years)
Patents	$	2,963	$	(2,049)	$	—	$	914	10
Developed technology - 150V	560		(517)		(43)		—		6
Developed technology - 600V	1,701		(1,570)		(131)		—		6
Total	$	5,224	$	(4,136)	$	(174)	$	914

The Company recorded amortization expenses related to intangible assets of $297 thousand for the year ended March 31, 2022, $74 thousand for the three months ended March 31, 2021 and $326 thousand for the year ended December 31, 2020.

Estimated future amortization expenses related to intangible assets as of March 31, 2022 were as follows (in thousands):


Year Ending March 31,
2023	$	296
2024	296
2025	25
Total	$	617

Investment in Joint Venture

12 Months Ended

Mar. 31, 2022

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Investment in Joint Venture

Through July 31, 2021, the Company was party to a joint venture agreement (the “JVA”), by and among Aizu Fujitsu Semiconductor Limited, Fujitsu Semiconductor Limited (“FSL”), the Company and Transphorm Aizu, Inc. (“Transphorm Aizu”) for the ownership and operations of Aizu Fujitsu Semiconductor Wafer Solution Limited (“AFSW”). Through July 31, 2021, the Company held a 49% interest in AFSW through Transphorm Aizu, the Company’s wholly-owned subsidiary established in Japan to manage the financial transactions around AFSW. Transphorm Aizu and FSL funded AFSW based on a mutually agreed funding schedule. Any outstanding balances were reviewed upon the conclusion of the JVA effective July 31, 2021 to assess unfunded commitment to joint venture liability. During the year ended March 31, 2022, the Company recognized a $1.5 million gain, in other income, upon termination of the JVA and settlement of its obligation.

On April 1, 2020, FSL exercised its put option under the JVA and notified the Company that FSL intended to exit the joint venture by selling its 51% interest in AFSW to the Company. In December 2020, the Company entered into a joint venture agreement with JCP Capital Management, LLC Limited (controlling party with 75%

ownership) to create GaNovation, a joint venture company in Singapore, to engage in the business of distribution, development and supply of GaN products and, upon approval of the regulatory authorities in Japan, to purchase FSL’s and Transphorm’s interests in AFSW. In July 2021, regulatory authorities in Japan approved GaNovation’s purchase of 100% of the interests in AFSW from Transphorm and FSL. On July 20, 2021, Transphorm Aizu entered into a Share Purchase Agreement (the “Purchase Agreement”) with GaNovation, pursuant to which GaNovation agreed to acquire Transphorm’s 49% interest in AFSW from Transphorm Aizu for 1 Japanese Yen. The closing of the Purchase Agreement occurred on August 1, 2021. Following the closing of the Purchase Agreement and other concurrent transactions between GaNovation and FSL, GaNovation owns 100% of AFSW and Transphorm now holds a 25% interest in GaNovation. For the year ended March 31, 2022, GaNovation’s primary business activity related to the businesses of AFSW. The Company and JCP Capital Management, LLC Limited (“JCP”) have agreed to use their best efforts to maintain the operations of AFSW until at least August 1, 2022.

GaNovation (through AFSW) manufactures semiconductor products exclusively for its owners under manufacturing agreements at prices estimated to cover the cost of production. GaNovation was determined to be a variable interest entity as the equity at risk was not believed to be sufficient. GaNovation depends on its owners for any additional cash. The Company extended $2.0 million and $2.5 million to GaNovation and AFSW to fund operations of GaNovation and AFSW, respectively, for the year ended March 31, 2022, and $968 thousand and $7.3 million to AFSW to fund AFSW’s operations for the three months ended March 31, 2021 and the year ended December 31, 2020, respectively. The Company’s known maximum exposure to loss approximated the carrying value of its investment balance, which included the financing. Potential future losses could be higher than the carrying amount of the Company’s investment, as the Company is liable for other future operating costs or obligations of GaNovation. In addition, because Transphorm is currently committed to purchasing GaN wafers and production-related services from AFSW at pre-agreed pricing based upon the Company’s second generation products, the Company may be required to purchase products at a higher cost for its newer generation products. Investment in GaNovation was $143 thousand as of March 31, 2022, and unfunded commitment to GaNovation was $1.9 million and $1.5 million as of March 31, 2021 and December 31, 2020, respectively.

JCP is responsible for 75% of the funding obligations and losses of AFSW, while Transphorm is responsible for 25% of the funding obligations and losses of AFSW for the period from April 1, 2022 through March 31, 2023 and JCP is responsible for 67.5% of the funding obligations and losses of AFSW, while Transphorm is responsible for 32.5% of the funding obligations and losses of AFSW for the period from April 1, 2023 and thereafter, except that JCP’s total funding obligations or investments shall not exceed $35 million and Transphorm’s total funding obligations or investment shall not exceed $12 million for the three year period starting from August 1, 2021.

The Company’s investment activities in GaNovation and AFSW for the periods presented are summarized below (in thousands):


AFSW (Joint Venture Between the Company and FSL)
January 1, 2020	$	(1,688)
Investment	7,348
Loss	(6,836)
Effect of exchange rate change	(290)
December 31, 2020	(1,466)
Investment	968
Loss	(1,468)
Effect of exchange rate change	100
March 31, 2021	(1,866)
Investment	2,490
Loss	(2,078)
Gain	1,455
Effect of exchange rate change	(1)
July 31, 2021	$	—

GaNovation (Joint Venture Between the Company and JCP)
August 1, 2021	$	—
Investment	2,036
Loss	(1,893)
Effect of exchange rate change	—
March 31, 2022	$	143

Summarized unaudited financial information of GaNovation and AFSW for the periods indicated are as follows (in thousands):


					GaNovation		AFSW
					March 31, 2022		March 31, 2021
Current assets					4,259		$	932
Long-term assets					3,690		$	5,330
Other current liabilities					3,799		$	2,200
Due to controlling owner					(1)		$	22,354
Due to Transphorm					—		$	13,179
Net surplus (deficit)					4,151		$	(31,471)

	GaNovation		AFSW
	For the Eight Months Ended March 31, 2022		For the Four Months Ended July 31, 2021		For the Three Month Transition Period Ended March 31, 2021		For the Year Ended December 31, 2020
Sales	$	6,933	$	2,176	$	842	$	2,976
Gross loss	$	(6,168)	$	(3,191)	$	(2,425)	$	(11,411)
Net loss	$	(7,707)	$	(4,260)	$	(2,995)	$	(13,952)

Debts

12 Months Ended

Mar. 31, 2022

Debt Disclosure [Abstract]

Debts

Development Loans

On April 4, 2018, the Company entered into a Loan and Security Agreement (“LSA”) and Development and License Agreement (“DLA”) with Nexperia. The LSA provided for term loans in an aggregate principal amount of up to $15.0 million, which term loans were available in tranches (Tranche A, Tranche B and Tranche B-1) and subject to the satisfaction of specified conditions. The Tranche A Loan of $5.0 million initially was scheduled to mature on the earlier of the date a specified report is required to be delivered under the DLA or March 31, 2020. On April 8, 2020, the maturity of the Tranche A loan was extended to April 30, 2020 and, on April 28, 2020, the maturity of the Tranche A Loan was further extended to June 30, 2020. On June 29, 2020, the Tranche A Loan of $5.0 million was satisfied in full when the Company transferred its Gen-4 technology development to Nexperia. The Tranche B Loan of $8.0 million and Tranche B-1 Loan of $2.0 million mature on the earlier of the date a specified report is required to be delivered under the DLA or March 31, 2021, subject to extension as provided in the LSA. On March 1, 2021, the maturity of the Tranche B Loan of $8.0 million and Tranche B-1 Loan of $2.0 million was extended to June 30, 2021. On May 18, 2021, Tranche B-1 Loan of $2.0 million was converted into a Tranche C-1 Loan, which Tranche C-1 Loan has the same terms and conditions as the existing Tranche C Loan. On June 30, 2021, the maturity of the Tranche B Loan was extended to July 16, 2021. On July 16, 2021, the Tranche B Loan of $8.0 million was satisfied in full when the Company transferred its Gen-5 and 900V technology developments to Nexperia. See Note 3 - Nexperia Arrangement.

As of March 31, 2022, March 31, 2021 and December 31, 2020, aggregate principal amount of term loans outstanding under the LSA were $0, $10.0 million and $10.0 million, respectively.

Revolving Credit Facility

The LSA also provided a $10.0 million revolving loan (Tranche C Loan) that was scheduled to mature at the earlier of (i) April 3, 2021, and (ii) the date a Change of Control (as defined in the LSA) of the Company occurs. Interest payable by the Company accrues on the outstanding principal amount of the loans during such period at a rate of 6% per annum. The credit facility is secured against certain of our U.S. patents not relating to MOCVD or epiwafer technology. On March 1, 2021, the maturity of the Tranche C Loan of $10.0 million was extended to May 18, 2021. On May 18, 2021, the maturity of the Tranche C Loan was extended to the earlier of April 4, 2023 and the occurrence of specified change of control events, and $2.0 million Tranche B-1 Loan converted into a Tranche C-1 Loan (the “Tranche C Loans” together with the Tranche C Loan) with the same terms and conditions as the existing Tranche C Loan. See Note 3 - Nexperia Arrangement.

The Tranche C Loans are recorded based on principal in the amount of $12.0 million and accrued interest (6% interest per annum). The Company recorded interest expense of $715 thousand for the year ended March 31, 2022, $150 thousand for the three months ended March 31, 2021 and $610 thousand for the year ended December 31, 2020. The Company paid interest expense of $685 thousand for the year ended March 31, 2022, $153 thousand for the three months ended March 31, 2021 and $915 thousand for the year ended December 31, 2020.

Promissory Note

The Company’s stated value of promissory note obligation as of the dates presented consists of the following (in thousands):


	Interest Rate	Due Date	March 31, 2022		March 31, 2021
Yaskawa Note	1.00%	September 2022	$	—	$	15,523

Pursuant to ASC 825-10-15-4, the Company elected to apply the fair value option for the promissory note. As of the dates presented, the Company determined the fair value for the note, as compared to the face value, including accrued interest, as follows (in thousands):


	March 31, 2022		March 31, 2021
Yaskawa Note	$	—	$	16,128

Fair value of promissory note decreased $605 thousand for the year ended March 31, 2022, increased $699 thousand for the three months ended March 31, 2021 and decreased $927 thousand for the year ended December 31, 2020.

In October 2017, the Company issued an unsecured subordinated convertible promissory note to Yaskawa (the “Yaskawa Note”) for $15.0 million. The stated interest rate of the Yaskawa Note was 1.0%, and principal plus interest was due on the earlier of September 30, 2022, or the date of the occurrence of an Event of Default, Change of Control or an Initial Public Offering (all terms as defined in the Yaskawa Note). In connection with the Merger, the Yaskawa Note was amended to be convertible at the option of the holder into a maximum of 3,076,171 shares of our common stock at a conversion price of $5.12 per share.

On October 4, 2021, the Company entered into a Note Amendment and Conversion Agreement with Yaskawa to (i) reduce the conversion price of the Yaskawa Note from $5.12 per share to $5.00 per share and (ii) remove the limitation on the maximum number of shares of the Company’s stock that could be issued upon conversion of the Yaskawa Note. Yaskawa simultaneously elected to convert the outstanding principal amount (plus accrued but unpaid interest) under the Yaskawa Note, which as of the effective date of the conversion totaled $15.6 million, into an aggregate of 3,120,000 shares of our common stock. The Company also issued to Yaskawa a warrant to purchase up to 650,000 shares of common stock at an exercise price of $6.00 per share with a term of three years. During the year ended March 31, 2022, the Company recognized $1.2 million gain, in other income, upon the conversion of the Yaskawa Note.

In connection with its promissory note obligation, the Company recorded interest expense of $77 thousand for the year ended March 31, 2022, $37 thousand for the three months ended March 31, 2021 and $150 thousand for the year ended December 31, 2020. In accordance with the terms of the promissory note, interest is added to the principal balance and is reflected in the carrying value on the consolidated balance sheet. As of March 31, 2022, March 31, 2021 and December 31, 2020, accrued interest on the promissory note was $0, $523 thousand and $486 thousand, respectively.

In December 2020, the Company entered into a cooperation and development agreement with Yaskawa, pursuant to which Yaskawa agreed to provide $4.0 million over approximately three years to fund development activities related to industrial power conversion applications, with an initial focus on servo motor drive applications. Yaskawa provided payments of $1.0 million and $750 thousand of this $4.0 million commitment in December 2020 and July 2021, respectively. Accordingly, with respect to the $1.8 million payment, the Company recognized $1.1 million as revenue for the year ended March 31, 2022, $333 thousand as revenue for the three months ended March 31, 2021 and $333 thousand as revenue for the year ended December 31, 2020. The Company also recorded $375 thousand as revenue for services rendered but not billed for the year ended March 31, 2022.

As of March 31, 2022, the scheduled maturity, including accrued interest, of the Company’s borrowings under the Tranche C Loans was as follows (in thousands):


Year Ending March 31,
2023	$	180
2024	12,000
Total	$	12,180

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-URI http://asc.fasb.org/topic&trid=2208564

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 1I
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-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
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-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 1E
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

+ Details

Commitments and Contingencies

12 Months Ended

Mar. 31, 2022

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Commitment with a Government Agency

In connection with a contract with a government agency, the Company entered into a commitment to acquire equipment and services from vendors totaling $7.4 million, all of which is reimbursable. The contract’s expiration date was March and June 2022 but such dates were subsequently extended to June and December 2022, respectively. The Company has made total purchases of $7.3 million cumulatively as of March 31, 2022, of which $7.2 million was reimbursed by the government agency as of March 31, 2022. During the year ended March 31, 2022, the Company made purchases of $369 thousand and the remaining accounts payable to the vendors was $131 thousand as of March 31, 2022.

In September 2021, the Company was awarded a $0.9 million contract with a $0.5 million option by a government agency for delivering epiwafer technology. The Company billed and received $211 thousand for the year ended March 31, 2022.

Operating Leases

The Company leases office and fabrication space in Goleta, California, and office space in Campbell, California and in Japan, China, Hong Kong, Taiwan and the Philippines under noncancelable operating lease agreements. The terms of certain leases provide for escalating rental payments through the term of the lease. The Company recognizes rent expense on a straight-line basis over the lease term and accrues for rent expense incurred but not paid.

As of March 31, 2022, future minimum operating lease commitments were as follows (in thousands):


Year Ending March 31,
2023	$	681
2024	647
2025	156
Total	$	1,484

The Company recorded rent expense, net of rental income, which includes common area maintenance fees in addition to the base rent, of $918 thousand for the year ended March 31, 2022, $212 thousand for the three months ended March 31, 2021 and $892 thousand for the year ended December 31, 2020. Rental income from a noncancelable sublease was $0 for the year ended March 31, 2022, $30 thousand for the three months ended March 31, 2021 and $182 thousand for the year ended December 31, 2020. As of March 31, 2022, there are no future minimum rental payments to be received under the noncancelable sublease.

Contingencies

During the ordinary course of business, the Company may become a party to legal proceedings incidental to its business. The Company accrues contingent liabilities when it is probable that future expenditures will be made and such expenditures can be reasonably estimated. Legal cost is expensed as incurred.

On April 5, 2022, Joel Newman, an alleged holder of the Company’s common stock, filed a complaint in the Delaware Court of Chancery derivatively against the Company’s directors and KKR Phorm Investors L.P. (“Phorm”). The complaint alleges that the directors and Phorm breached their fiduciary duties, and the directors committed waste, because the terms of the November 5, 2021 private placement in which Phorm participated were unfairly favorable to Phorm. The directors have the right to advancement from the Company of expenses incurred defending the claims. The defendants filed motions to dismiss on May 26, 2022. The Company is unable to estimate the potential loss or range of loss, if any, associated with this lawsuit.

The Company is not aware of any material legal claims or assessments other than disclosed above. Although the results of litigation and claims are inherently unpredictable, management believes there was not at least a reasonable possibility that the Company had incurred a material loss with respect to any loss contingencies as of March 31, 2022 and through the issuance of these financial statements.

Indemnification

The Company from time to time enters into types of contracts that contingently require the Company to indemnify parties against third-party claims. These contracts primarily relate to: (1) real estate leases, under which the Company may be required to indemnify property owners for environmental and other liabilities and for other claims arising from the Company’s use of the applicable premises; (2) agreements with the Company’s officers, directors, and employees, under which the Company may be required to indemnify such persons from liabilities arising out of their relationship; (3) indemnifying customers in the event of product failure; and (4) agreements with outside parties that use the Company’s intellectual property, under which the Company may indemnify for copyright or patent infringement related specifically to the use of such intellectual property.

Historically, the Company has not been required to make payments under these obligations, and no liabilities have been recorded for these obligations in the Company’s consolidated financial statements.

Stockholders' Equity (Deficit)

12 Months Ended

Mar. 31, 2022

Equity [Abstract]

Stockholders' Equity (Deficit)

Stockholders’ Equity (Deficit)

On February 12, 2020, in connection with the Merger, shares of Transphorm Technology’s convertible preferred stock and common stock issued and outstanding immediately prior to the closing of the Merger were converted into shares of the Company’s common stock as follows:

•Series 1 convertible preferred stock: 51,680,254 shares issued and outstanding were converted into 12,433,953 shares issued and outstanding;

•Series 2 convertible preferred stock: 38,760,190 shares issued and outstanding were converted into 7,499,996 shares issued and outstanding;

•Series 3 convertible preferred stock: 31,850,304 issued and outstanding were converted into 4,000,000 shares issued and outstanding; and

•Common stock: 50,325,662 shares issued and outstanding were converted into 4,171,571 shares, net of 52,733 redeemed shares from unaccredited investors, issued and outstanding.

In addition, on February 12, 2020, the Company issued 1,650,000 shares in connection with the Merger with Peninsula Acquisition Corporation.

All per share and share amounts for all periods presented have been retroactively adjusted to reflect the effect of the Merger.

In April 2021, the Company issued 97,099 shares of common stock as payment of $500 thousand pursuant to a one year internet advertising contract with SRAX, Inc.

In October 2021, the Company issued 3,120,000 shares of common stock to Yaskawa upon the conversion of $15.6 million of outstanding principal and accrued interest under the Yaskawa Note.

In January and February 2022, the Company withheld 97,249 shares of common stock upon the vesting of restricted stock units to satisfy employee withholding tax obligations.

As of March 31, 2022, 750,000,000 shares of common stock are authorized, of which 53,379,307 shares of common stock were issued and outstanding, and 5,000,000 shares of preferred stock are authorized, none of which

were issued and outstanding. The Company’s Board of Directors has the ability to designate the rights, preferences and privileges for the preferred stock.

Private Placements

On February 12, 2020 and February 27, 2020, the Company sold an aggregate of 5,380,000 shares of common stock in a private placement offering at a purchase price of $4.00 per share, with aggregate gross proceeds of $21.5 million (before deducting placement agent fees and other offering expenses, which were an aggregate of $1.8 million).

On December 23, 2020, the Company sold an aggregate of 5,000,000 shares of common stock in a private placement offering at a purchase price of $3.00 per share and issued warrants to placement agents to purchase 150,000 shares of common stock at a price of $3.30 per share, with aggregate gross proceeds of $15.0 million (before deducting placement agent fees, financial advisor fees and other offering expenses, which were an aggregate of $1.4 million excluding warrant cost of $223 thousand).

On March 31, 2021, the Company sold 250,000 shares of common stock in a private placement offering at a purchase price of $4.00 per share, with gross proceeds of $1.0 million (before deducting placement agent fees and other offering expenses, which were an aggregate of $50 thousand).

On August 13, 2021, the Company sold 1,000,000 shares of common stock in a private placement offering at a purchase price of $5.00 per share with gross proceeds of $5.0 million and issued warrants to purchase 209,000 shares of common stock at a price of $6.00 per share (before deducting legal costs of $22 thousand).

On November 5, 2021 and November 9, 2021, the Company sold an aggregate of 6,600,000 shares of common stock in a private placement offering at a purchase price of $5.00 per share, with aggregate gross proceeds of $33.0 million (before deducting placement agent fees and other offering expenses, which were an aggregate of $840 thousand). Pursuant to the purchase agreements entered into with the investors in this offering, each investor had the right (but not the obligation), subject to the satisfaction of customary closing conditions, to purchase and acquire from the Company (i) additional shares of common stock at a purchase price of $5.00 per share and (ii) additional warrants to purchase shares of common stock. On June 2, 2022, in connection with the investors’ exercise of such purchase rights, the Company sold 3,199,999 shares of common stock for aggregate gross proceeds of $16.0 million (before deducting placement agent fees and other offering expenses, which were an aggregate of $280 thousand) and issued warrants to purchase 666,668 shares of common stock.

On December 7, 2021, the Company sold 1,673,152 shares of common stock in a private placement offering at a purchase price of $7.71 per share, with aggregate gross proceeds of $12.9 million (before deducting a finder’s fee and other offering expenses, which were an aggregate of $286 thousand).

Common Stock

Common stockholders are entitled to dividends, as and when declared by the Company’s Board of Directors, subject to the priority dividend rights of the holders of other classes of stock. There have been no dividends declared to date. The holder of each share of common stock is entitled to one vote.

The Company has reserved shares of common stock for future issuance as of date presented as follows:


			March 31, 2022
Equity incentive plans			6,707,843
Common stock warrants			2,657,298
Total			9,365,141

Common Stock Warrants

On December 23, 2020, we issued warrants to purchase 150,000 shares of common stock at an exercise price of $3.30 per share. On August 13, 2021, we issued warrants to purchase 209,000 shares of common stock at an exercise price of $6.00 per share. On October 4, 2021, we issued warrants to purchase 650,000 shares of common stock at an exercise price of $6.00 per share. On November 5, 2021, we issued warrants to purchase 958,334 shares of common stock at an exercise price of $6.00 per share. On November 9, 2021, we issued warrants to purchase 416,667 shares of common stock at an exercise price of $6.00 per share. On December 7, 2021, we issued warrants to purchase 348,649 shares of common stock at an exercise price of $9.25 per share. On February 10, 2022, we issued warrants to purchase 20,233 shares of common stock at an exercise price of $8.48 per share. These warrants are exercisable by paying cash or by cashless exercise for unregistered shares of common stock. The exercise price of the warrants is subject to standard antidilutive provision adjustment in the case of stock dividends or other distributions on shares of common stock or any other equity or equity equivalent securities payable in shares of common stock, stock splits, stock combinations, reclassifications or similar events affecting our common stock, and also, subject to limitations, upon any distribution of assets, including cash, stock or other property to our stockholders. The exercise price of the warrants is not subject to “price-based” anti-dilution adjustment. We have determined that these warrants related to issuance of common stock are subject to equity treatment because warrant holders have no right to demand cash settlement and there are no unusual anti-dilution rights.

On January 5, 2022, the Company issued 13,028 shares of common stock in connection with the cashless exercise of a warrant. On January 10, 2022, the Company issued 82,500 shares of common stock in connection with the exercise of a warrant at an exercise price of $3.30 per share.

The following warrants to purchase common stock were outstanding as of March 31, 2022:


Number of Shares	Exercise Price		Expiration Date
6,046	$	34.74	5 years after an initial public offering of the Company
3,369	$	54.41	5 years after an initial public offering of the Company
45,000	$	3.30	December 23, 2025
209,000	$	6.00	August 13, 2024
650,000	$	6.00	October 4, 2024
958,334	$	6.00	November 5, 2024
416,667	$	6.00	November 9, 2024
348,649	$	9.25	December 7, 2024
20,233	$	8.48	December 10, 2025
2,657,298

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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-Publisher FASB
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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+ Details

Stock-Based Compensation

12 Months Ended

Mar. 31, 2022

Share-based Payment Arrangement [Abstract]

Stock-Based Compensation

Stock-Based CompensationThe 2020 Equity Incentive Plan (the “2020 Plan”) was approved by Transphorm Technology’s board of directors on February 10, 2020 and Transphorm Technology’s stockholders on February 12, 2020, and became effective on the business day immediately prior to the closing of the Merger. Our stockholders approved the 2020 Plan on February 11, 2020. We assumed the 2020 Plan in connection with the Merger. The 2020 Plan provides for the grant of incentive stock options, within the meaning of Section 422 of the Internal Revenue Code of 1986, as amended (the “Code”), to our employees and our parent and subsidiary corporations’ employees, and for the grant of nonstatutory stock options, stock appreciation rights, restricted stock, restricted stock units (“RSUs”), performance units, and performance shares to our employees, directors, and consultants and our parent and subsidiary corporations’ employees and consultants. As of March 31, 2022, there were 2,879,008 stock options outstanding, 954,775 restricted stock units outstanding and 2,874,060 shares available for grant under the 2020 Plan. During the

year ended March 31, 2022, 2,026,599 shares were added to the 2020 Plan pursuant to an automatic annual increase provision in the plan.

Subject to the adjustment provisions of the 2020 Plan, and the automatic increase described in the 2020 Plan, the maximum aggregate number of shares of our common stock that may be issued under the 2020 Plan is 5,050,000 shares of our common stock, which includes (i) 2,588,077 shares initially reserved for issuance, plus (ii) any shares of our common stock subject to issued and outstanding awards under the 2007 Plan or 2015 Plan that were assumed in the Merger and that, on or after the closing of the Merger, expire or otherwise terminate without having been exercised or issued in full, are tendered to or withheld by us for payment of an exercise price or for tax withholding obligations, or are forfeited to or repurchased by us due to failure to vest, with the maximum number of shares to be added to the 2020 Plan pursuant to this clause (ii) equal to 2,461,923 shares. Subject to the adjustment provisions of the 2020 Plan, the number of shares of common stock available for issuance under the 2020 Plan will also include an annual increase on the first day of each fiscal year beginning with our 2022 fiscal year and ending on (and including) our 2030 fiscal year, in an amount equal to the least of: 5,000,000 shares of our common stock; five percent (5%) of the outstanding shares of our common stock on the last day of the immediately preceding fiscal year; or such number of shares of our common stock as the administrator of the 2020 Plan may determine.

Stock Options

The following table summarizes stock option activity and related information for the periods presented:


	Number of Options	Weighted Average Exercise Price per Share		Weighted Average Remaining Contractual Term (in Years)	Aggregate Intrinsic Value (1) (in thousands)
Outstanding at January 1, 2020	2,473,198	$	4.67	6.84	$	—
Options granted	—	$	—
Options exercised	(6,821)	$	3.78
Options canceled	(146,059)	$	5.88
Outstanding at December 31, 2020	2,320,318	$	4.67	5.92	$	—
Exercisable at December 31, 2020	2,267,154	$	4.70	5.86	$	—

Outstanding at January 1, 2021	2,320,318	$	4.67	5.92	$	—
Options granted	223,638	$	6.37
Options exercised	(500)	$	3.14
Options canceled	(331)	$	9.29
Outstanding at March 31, 2021	2,543,125	$	4.82	6.05	$	—
Exercisable at March 31, 2021	2,283,243	$	4.70	5.65	$	—

Outstanding at April 1, 2021	2,543,125	$	4.82	6.05	$	—
Options granted	528,077	$	6.31
Options exercised	(52,799)	$	4.19
Options canceled	(139,395)	$	9.52
Outstanding at March 31, 2022	2,879,008	$	4.88	6.02	$	6,747
Exercisable at March 31, 2022	2,206,259	$	4.44	4.99	$	5,984

(1) Intrinsic value represents the excess of the fair value on the last day of the period (which was $7.07, $3.75 and $3.01 as of March 31, 2022, March 31, 2021 and December 31, 2020, respectively) over the exercise price, multiplied by the number of options.

Stock-based compensation expense is determined based on the fair value of the Company’s common stock as determined by the Board of Directors and assumptions such as volatility, expected term, risk-free interest rates, and other factors. Changes in the deemed fair value of the common stock, the underlying assumptions in the calculations, the number of options granted or the terms of such options, the expected forfeiture rate, the treatment of tax benefits and other changes may result in significant differences in the amounts or timing of the compensation expense recognized. The assumptions and estimates are made as follows:

•Expected Volatility - The Company utilizes the historical volatility of representative public companies to determine its expected volatility, as the trading history of the Company’s common stock is limited.

•Estimated Forfeitures - The Company adopted ASU 2016-09, Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting and has elected to account for forfeitures as they occur and therefore, stock-based compensation expense has been calculated based on actual forfeitures in the statements of operations, rather than our previous approach which was net of estimated forfeitures. The net cumulative effect of this change was not material.

•Expected Dividend Yield - The Company has not issued any common stock dividends; therefore, a dividend yield of zero was used.

•Risk-Free Interest Rate - The Company bases the risk-free interest rate used in the Black-Scholes-Merton option pricing model on the implied yield currently available on United States Treasury zero-coupon issues with an equivalent expected term.

•Expected Term - The expected term of stock options represents the period that the Company’s stock options are expected to be outstanding. The Company generally uses the simplified method to calculate the expected term for employee grants.

The assumptions used to value options granted to employees during the periods presented was as follows:


	Year Ended March 31, 2022	Three Month Transition Period Ended March 31, 2021
Weighted average expected life (in years)	5.87	5.23
Risk-free interest rate	1.08% - 1.32%	0.78% - 1.73%
Expected volatility	42.5% - 43.8%	43.1% - 44.3%
Grant date fair market value	$6.34	$3.75
Grant date fair value	$1.94 - $3.32	$0.94 - $1.65
Dividend yield	—%	—%

Restricted Stock

Restricted Stock Awards

RSAs are grants of shares of our common stock that vest in accordance with terms and conditions established by the Company’s Board of Directors. Recipients of RSAs generally will have voting and dividend rights with respect to such shares upon grant without regard to vesting, unless the RSA agreement provides otherwise. Shares of restricted stock that do not vest are subject to forfeiture. In September 2020, we granted 123,501 RSAs outside of our 2020 Plan, 98,450 of which were fully vested on the date of grant and the remainder of which vested in January 2021. In December 2020, we granted 12,000 RSAs outside of our 2020 Plan, all of which were fully vested on the date of grant. There were no RSAs outstanding as of March 31, 2021 and no RSA activities during the year ended March 31, 2022.

The following table summarizes RSA activity and related information for the periods presented:


	Number of Shares	Weighted-Average Grant Date Fair Value Per Share
January 1, 2020	—	$	—
Granted	135,501	$	3.91
Vested	(98,450)	$	3.88
December 31, 2020	37,051	$	4.00
Granted	—	$	—
Vested	(37,051)	$	4.00
March 31, 2021	—	$	—
Granted	—	$	—
Vested	—	$	—
March 31, 2022	—	$	—

Restricted Stock Units

RSUs are grants of shares of our common stock that vest in accordance with terms and conditions established by the administrator of the 2020 Plan. Subject to the provisions of the 2020 Plan, the administrator determines the terms and conditions of RSUs, including the vesting criteria. We granted 816,180 RSUs during the three months ended September 30, 2020, 4,000 of which were fully vested on the date of grant. The remainder of the RSUs are scheduled to vest as follows: one third will vest on each of January 1, 2022, January 1, 2023 and July 1, 2023, in each case subject to the RSU holders’ continued status as a service provider to the Company through each vesting date. We granted 137,452 RSUs during the three months ended March 31, 2021, which are scheduled to vest in various periods, beginning immediately and ending on February 2025, in each case subject to the RSU holders’ continued status as a service provider to the Company through each vesting date. We granted 35,000 RSUs during the three months ended September 30, 2021, 25 percent of which are scheduled to vest after one year and the remainder are scheduled to vest each quarter for three years, in each case subject to the RSU holders’ continued status as a service provider to the Company through each vesting date. We granted 307,640 RSUs during the three months ended December 31, 2021, 25% of which are scheduled to vest annually over four years on each anniversary of the vesting commencement date, in each case subject to the RSU holders’ continued status as a service provider to the Company through the applicable vesting date.

The following table summarizes RSU activity and related information for the periods presented:


	Number of Shares	Weighted-Average Grant Date Fair Value Per Share
January 1, 2020	—	$	—
Granted	816,180	$	4.00
Vested	(4,000)	$	4.00
Canceled	(6,855)	$	4.00
December 31, 2020	805,325	$	4.00
Granted	137,452	$	3.75
Vested	(3,000)	$	3.75
Canceled	(4,380)	$	4.00
March 31, 2021	935,397	$	3.96
Granted	342,640	$	6.31
Vested	(305,982)	$	3.98
Canceled	(17,280)	$	3.98
March 31, 2022	954,775	$	4.61

Stock-Based Compensation

The accompanying consolidated statement of operations and comprehensive loss includes stock-based compensation expense for the periods presented as follows (in thousands):


	Year Ended March 31, 2022		Three Month Transition Period Ended March 31, 2021		Year Ended December 31, 2020
Cost of revenue	$	161	$	39	$	93
Research and development	552		115		306
Sales and marketing	190		33		68
General and administrative	1,711		326		1,058
Total	$	2,614	$	513	$	1,525

Unrecognized Stock-Based Compensation

Unrecognized stock-based compensation expense as of dates presented was as follows (in thousands):


	March 31, 2022			March 31, 2021
	Unrecognized Expense		Average Expected Recognition Period (in years)	Unrecognized Expense		Average Expected Recognition Period (in years)
Stock options	$	1,413	2.11	$	280	5.06
Restricted stock	2,576		1.57	2,738		1.76
Total	$	3,989	1.76	$	3,018	2.07

Fair Value Measurements

12 Months Ended

Mar. 31, 2022

Fair Value Disclosures [Abstract]

Fair Value Measurements

Fair Value MeasurementsFASB ASC 820, Fair Value Measurements and Disclosures, establishes a three-tier fair value hierarchy for disclosure of fair value measurements as follows:

Level 1 - Unadjusted quoted prices in active markets for identical assets and liabilities.

Level 2 - Inputs (other than quoted prices included within Level 1) that are observable, unadjusted quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data of substantially the full term of the related assets or liabilities.

Level 3 - Inputs reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. Inputs are unobservable for the asset or liability. Consideration is given to the risk inherent in the valuation technique and the risk inherent in the inputs to the model.

The categorization of a financial instrument within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The following table summarizes the Company’s liabilities measured at fair value as of the dates presented, by level within the fair value hierarchy (in thousands):


	Level 1		Level 2		Level 3
March 31, 2022
Promissory note	$	—	$	—	$	—
March 31, 2021
Promissory note	$	—	$	—	$	16,128

The following table includes the changes in fair value of the promissory note which are Level 3 on the fair value hierarchy (in thousands):


January 1, 2020	$	16,169
Interest expense accrued	150
Decrease in fair value	(927)
December 31, 2020	15,392
Interest expense accrued	37
Increase in fair value	699
March 31, 2021	16,128
Interest expense accrued	77
Decrease in fair value	(605)
Conversion	(15,600)
March 31, 2022	$	—

On October 4, 2021, the promissory note of $15.6 million, consisting of an outstanding principal amount of $15.0 million plus accrued but unpaid interest of $600 thousand, was converted into an aggregate of 3,120,000 shares of common stock. See Note 9 - Debts and Note 11 - Stockholders’ Equity (Deficit).

The Company recorded interest expense of $77 thousand for the year ended March 31, 2022, $37 thousand for the three months ended March 31, 2021 and $150 thousand for the year ended December 31, 2020. Fair value of promissory note decreased by $605 thousand for the year ended March 31, 2022, increased $699 thousand for the three months ended March 31, 2021 and decreased $927 thousand for the year ended December 31, 2020.

Level 3 borrowings, which consist of promissory note, are measured and reported at fair value using a Monte Carlo simulation valuation model. The models can include assumptions related to the value of the notes that are based on the estimated timing and amounts of future rounds of financing, including the estimated timing of a change in control of the Company, and estimated market interest rates, which represent significant unobservable inputs. Assumptions used are (1) the Company is worth today what it can generate in future cash to the Company,

(2) cash received today is more than an equal amount of cash received in the future, and (3) future cash flows can be reasonably estimated.

The following table summarizes assumptions used for fair value of promissory note as of the dates presented:


			March 31, 2021
Stock price			$3.75
Time			1.5 years
Risk-free rate			0.12%
Volatility			50.6%

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

401(k) Savings Plan	12 Months Ended
401(k) Savings Plan	Mar. 31, 2022
Retirement Benefits [Abstract]
401(k) Savings Plan	401(k) Savings PlanThe Company has a 401(k) savings plan (the 401(k) plan). The 401(k) plan is a defined contribution plan intended to qualify under Section 401(k) of the Internal Revenue Code. All full-time employees of the Company are eligible to participate pursuant to the terms of the 401(k) plan. Contributions by the Company are discretionary, and the Company made no contributions during the year ended March 31, 2022, the three months ended March 31, 2021 and the year ended December 31, 2020.

- Definition

The entire disclosure for retirement benefits.

+ References

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+ Details

Income Taxes

12 Months Ended

Mar. 31, 2022

Income Tax Disclosure [Abstract]

Income Taxes

For the year ended March 31, 2022, the Company reported a worldwide consolidated pre-tax loss of $10.2 million, which consisted of a pre-tax loss from U.S. operations of approximately $8.8 million and pre-tax loss from Japan operations of approximately $1.4 million. The pre-tax loss from Japan operations consists of $1.2 million from Transphorm Japan, Inc., $627 thousand pre-tax loss from Transphorm Aizu, Inc. and $344 thousand pre-tax income from Transphorm Japan Epi, Inc.

For the three months ended March 31, 2021, the Company reported a worldwide consolidated pretax loss of $6.6 million, which consisted of a pre-tax loss from U.S. operations of approximately $4.9 million and pre-tax loss from Japan operations of approximately $1.7 million. The pre-tax loss from Japan operations primarily consists of $1.5 million from Transphorm Aizu, Inc. with nominal pre-tax book loss from Transphorm Japan, Inc. and Transphorm Japan Epi, Inc.

For the year ended December 31, 2020, the Company reported a worldwide consolidated pretax loss of $17.9 million, which consisted of a pre-tax loss from U.S. operations of approximately $10.3 million and pre-tax loss from Japan operations of approximately $7.6 million. The pre-tax loss from Japan operations consists of $800 thousand from Transphorm Japan, Inc., $6.8 million pre-tax loss from Transphorm Aizu, Inc. and $25 thousand pre-tax income from Transphorm Japan Epi, Inc.

There is no U.S. federal or foreign provision for income taxes because the Company has incurred operating losses since inception and is in a full valuation allowance position. For the year ended March 31, 2022, the three months ended March 31, 2021, and the year ended December 31, 2020, the Company recorded a state income tax provision of $1 thousand which represents minimum taxes. Deferred income taxes reflect the net tax effects of the net operating losses and the temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes.

Significant components of the Company’s deferred tax assets and deferred tax liabilities as of the dates presented as follows (in thousands):


	March 31, 2022		March 31, 2021
Deferred tax assets:
Net operating loss carryforwards	$	49,715	$	47,424
Tax credits	6,171		5,444
California capitalized research and development	40		72
Others, net	564		581
Total deferred tax assets	56,490		53,521
Valuation allowance	(56,550)		(53,481)
Deferred tax asset, net of valuation allowance	(60)		40
Deferred tax liabilities:
Fixed assets	60		(40)
Total deferred tax liabilities	60		(40)
Net deferred tax assets	$	—	$	—

As of March 31, 2022 and March 31, 2021, the Company had no assurance that future taxable income would be sufficient to fully utilize the net operating loss carryforwards and other deferred tax assets in the future. Consequently, the Company determined that a valuation allowance of approximately $56.6 million and $53.5 million as of March 31, 2022 and March 31, 2021, respectively, was needed to offset the deferred tax assets resulting mainly from the net operating loss carryforwards.

The Company files income tax returns in the U.S. federal, California, and Oregon jurisdictions and is subject to U.S. federal, state, and local income tax examinations by tax authorities. Generally, the statute of limitations is 3 years for U.S. federal income tax and 4 years for state and local taxes. The statute of limitations may be extended for tax years where a corporation has a net operating loss carryforward or by agreement with the jurisdictional taxing authority. Accordingly, all of the Company's U.S. federal, state and local income tax years since inception remain open to examination by tax authorities. The Company is not currently under audit by any taxing authority.

The Company follows the provisions of uncertain tax positions as addressed in ASC 740-10. The Company recognized no increase or decrease in the liability for unrecognized tax benefits for any period presented. The Company recognizes interest accrued related to unrecognized tax benefits in interest expense and penalties in operating expenses. No such interest or penalties were recognized during the period presented. The Company had no accruals for interest and penalties at March 31, 2022 and March 31, 2021.

The utilization of the Company’s net operating loss and tax credit carryforwards is dependent on the future profitability of the Company. Further, the Internal Revenue Code imposes substantial restrictions on the utilization of such carryforwards in the event of an ownership change of more than 50%, as defined, during any three-year period (Section 382 and 383 limitations). The Company has determined that several ownership changes have occurred, which have resulted in substantial limitations on the Company’s ability to utilize its pre-ownership change net operating loss and tax credit carryforwards. These substantial limitations are expected to result in both a permanent loss of certain tax benefits related to net operating loss carryforwards and federal research and development credits, as well as an annual utilization limitation. As of March 31, 2022, the Company performed an analysis for amounts that could be subject to Section 382 and 383 limitations and management did not believe such limitations existed. However, it is important to note that the Company continues to raise capital and such transaction could have an effect of such limitations. See Note 17 - Subsequent Events.

The federal net operating loss generated for the year ended March 31, 2022 of $9.8 million, for the three months ended March 31, 2021 of $4.5 million and for the year ended December 31, 2020 of $10.5 million can be carried forward indefinitely. However, the federal deduction for net operating losses incurred in tax years beginning after January 1, 2021 is limited to 80% annual taxable income. Under the Coronavirus Aid, Relief, and Economic Security Act (“CARES Act”), the suspension of net operating losses generated in years 2018, 2019, 2020 and 2021 are not subject to the 80% limitation. The state net operating loss generated for the year ended March 31, 2022 of $2.6 million, for the three months ended March 31, 2021 of $1.0 million, and for the year ended December 31, 2020 of $2.6 million can be carried forward 20 years.

As of March 31, 2022, the Company has federal net operating loss carryforwards of $258.9 million, of which $207.5 million will begin to expire in 2027 unless previously utilized, and the Company has state net operating loss carryforwards of $154.0 million which will begin to expire in 2028 unless previously utilized. The Company also has foreign net operating loss carryforwards of approximately $6.5 million which will begin to expire in 2024. As of March 31, 2022, the Company has federal research and development credit carryforwards of $5.0 million, which will begin to expire in 2032 unless previously utilized, and the Company had California research and development credit carryforwards of $4.3 million, which do not expire.

Deferred tax assets have not been established for net operating and tax credit carryforwards that are deemed to have no value due to the Section 382 and 383 limitations discussed above and, therefore, are not reflected in the table of deferred tax assets presented above. Future ownership changes, if any, may further limit the Company’s ability to utilize its remaining net operating losses and tax credit carryforwards. The Company performed an analysis as of March 31, 2022 and it was determined that no further limitations on tax attributes were required.

Reconciliation between federal statutory tax rate and the effective tax rate is shown in the following table for the periods presented:


	Year Ended March 31, 2022		Three Month Transition Period Ended March 31, 2021		Year Ended December 31, 2020
Federal statutory income tax rate	21.00	%	21.00	%	21.00	%
Research and development credit	7.10	%	2.73	%	4.06	%
Nondeductible expense	1.80	%	(2.43)	%	0.64	%
Loss in joint venture	(1.87)	%	(6.76)	%	(11.70)	%
Foreign income tax rate difference	1.39	%	2.45	%	4.10	%
Others, net	(0.40)	%	0.85	%	(2.08)	%
Valuation allowance	(29.02)	%	(17.84)	%	(16.02)	%
Effective tax rate	—	%	—	%	—	%

On March 27, 2020, the CARES Act was signed into law. The CARES Act repealed the 80% taxable income limitation for the 2018–2020 taxable years and reinstated NOL carrybacks for the 2018–2020 taxable years. In addition, the CARES Act temporarily increases the business interest deduction limitations from 30% to 50% of adjusted taxable income for the 2019 and 2020 taxable year. Lastly, a TCJA technical correction that classifies qualified improvement property as 15-year recovery period, allowing the bonus depreciation deduction to be claimed for such property retroactive as if it was included in the TCJA at the time of enactment.

On December 21, 2020, the Consolidated Appropriations Act (“CAA”) was signed into law. We do not expect any of the enactments of the CAA to have a material impact on the Company as of March 31, 2022.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Related Party Transactions	12 Months Ended
Related Party Transactions	Mar. 31, 2022
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions During the year ended March 31, 2022, the Company entered into the following related party transactions: •Recorded $476 thousand in revenue, recorded $1.5 million as gain in other income, recorded $3.1 million in cost of goods sold for services, recorded $12 thousand service expense, recorded $456 thousand in research and development expense, purchased $181 thousand of inventory, paid $140 thousand in consumption tax and incurred $343 thousand for employees and related benefits from the joint venture; •Sold $19 thousand of products to non-controlling stockholders of the Company, incurred $111 thousand of license maintenance fee and recorded $176 thousand in consulting expense from a non-controlling stockholder of the Company; •Recorded $1.5 million in revenue per a cooperation and development agreement with Yaskawa and $1.2 million gain in other income on Yaskawa promissory note conversion; and •Recorded $8.5 million in license fee income, recorded $150 thousand of reimbursements in license maintenance fee, recorded $714 thousand in interest expense, and sold $1.7 million of products to Nexperia. See Note 3 - Nexperia Arrangement. As of March 31, 2022, total due from related parties was $1.2 million, consisting of $719 thousand due from the joint venture and $515 thousand accounts receivable from a stockholder and noteholder of the Company. As of March 31, 2022, total accounts payable to related parties was $760 thousand to the joint venture and $102 thousand to Nexperia. During the three months ended March 31, 2021, the Company entered into the following related party transactions: • Recorded $406 thousand in cost of goods sold for services, recorded $144 thousand in research and development expense and incurred $9 thousand for employee and their benefits from the joint venture from AFSW; • Sold $12 thousand of products to non-controlling stockholders of the Company and incurred $54 thousand of license maintenance fee from a non-controlling stockholder of the Company; and • Recorded $357 thousand in license fee income, recorded $38 thousand of reimbursements in license maintenance fee, recorded $150 thousand in interest expense and sold $304 thousand of products to a stockholder and noteholder of the Company. See Note 3 - Nexperia Arrangement. As of March 31, 2021, total due from related parties was $14.1 million, consisting of $13.5 million due from the AFSW joint venture, $5 thousand accounts receivable from non-controlling stockholders of the Company, and $503 thousand accounts receivable from a stockholder and noteholder of the Company. As of March 31, 2021, total accounts payable to related parties was $370 thousand to the AFSW joint venture and $11 thousand to Nexperia, and accrued royalty was $4 thousand to Furukawa. During the year ended December 31, 2020, the Company entered into the following related party transactions: •Recorded $241 thousand in cost of goods sold for services, recorded research and development expense of $919 thousand, of which $408 thousand was reimbursable and recorded $84 thousand in other expense for commitment for services from the AFSW joint venture; •Sold $165 thousand of products to non-controlling stockholders of the Company and incurred $200 thousand of license maintenance fee from a non-controlling stockholder of the Company; and •Recorded $5.2 million in license fee income, recorded $701 thousand in EPI Gen 4 wafer growth sales, recorded $150 thousand of reimbursements in license maintenance fee, recorded $610 thousand in interest expense, recorded $408 thousand reimbursement for research and development, and sold $915 thousand of products to a stockholder and noteholder of the Company. See Note 3 - Nexperia Arrangement.

Subsequent Events	12 Months Ended
Subsequent Events	Mar. 31, 2022
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsOn June 2, 2022, in connection with the exercise of rights to purchase additional shares of common stock that were granted to investors who participated in the Company’s private placement completed in November 2021, the Company sold 3,199,999 shares of common stock for aggregate gross proceeds of $16.0 million (before deducting placement agent fees and other offering expenses, which were an aggregate of $280 thousand) and issued warrants to purchase 666,668 shares of common stock.

Summary of Significant Accounting Policies (Policies)	12 Months Ended
Summary of Significant Accounting Policies (Policies)	Mar. 31, 2022
Accounting Policies [Abstract]
Principles of Consolidation	The consolidated financial statements include the accounts of the Parent and its wholly-owned subsidiaries, Transphorm Technology, Transphorm Japan, Inc., Transphorm Japan Epi, Inc. and Transphorm Aizu, Inc. Upon consolidation, all significant intercompany accounts and transactions have been eliminated.
Use of Estimates	The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Management bases its estimates and assumptions on historical experience, knowledge of current conditions, and its belief of what could occur in the future, given available information. Actual results could differ from those estimates, and such differences could be material to the consolidated financial statements. Estimates are used for, but not limited to, the determinations of fair value of stock awards and promissory notes, accrual of expenses, revenue recognition, allowance for doubtful accounts, inventory reserve, and useful lives for property and equipment.
Cash, Cash Equivalents and Restricted Cash	The Company considers all highly-liquid investments with original maturities of 90 days or less at the date of purchase to be cash equivalents. Cash and cash equivalents consist principally of bank deposits and money market funds.
Foreign Currency Risk	The Company is exposed to foreign currency risk due to its operations in Japan (Yen). Assets and liabilities of the operations are re-measured into U.S. currency at exchange rates in effect at the balance sheet dates through the consolidated statements of comprehensive income. Gains or losses resulting from foreign currency transactions are re-measured using the rates on the dates on which those elements are recognized during the period and are included in other income or expense in the consolidated statements of operations.
Concentrations of Risk	Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash and cash equivalents. The Company is exposed to credit risk in the event of default by the financial institution holding its cash. The Company’s investment policy restricts investments to high-quality investments and limits the amounts invested with any one issuer, industry or geographic area. Risks associated with cash holdings in excess of insured limits are mitigated by banking with high-quality institutions. To date, the Company has not experienced any significant losses on its cash and cash equivalents. The Company periodically evaluates the relative credit standing of these financial institutions. The Company is subject to risks common in the power conversion components industry, including, but not limited to, technological obsolescence, dependence on key personnel, market acceptance of its products, the successful protection of its proprietary technologies, compliance with government regulations, and the possibility of not being able to obtain additional financing when needed.
Comprehensive Loss	Comprehensive loss is comprised of net loss and other comprehensive loss. Other comprehensive loss includes the impact of foreign currency translation adjustments.
Accounts Receivable	Accounts receivable are analyzed and allowances for uncollectible accounts are recorded, as required. Provisions for uncollectible accounts, if any, are recorded as bad debt expense and included in general and administrative expenses in the accompanying consolidated statements of operations. The process for determining the appropriate level of allowances for doubtful accounts involves judgment, and the Company considers such factors as the age of the underlying receivables, historical and projected collection trends, the composition of outstanding receivables, current economic conditions and regulatory changes. An account is fully reserved when reasonable collection efforts have been unsuccessful and it is probable that the receivable will not be recovered.
Inventory	Inventory is stated at the lower of cost (first-in, first-out method) or net realizable value. The Company periodically reviews the value of items in inventory and records write-downs or write-offs based on its assessment of slow moving or obsolete inventory. The Company maintains an inventory reserve for obsolete inventory and generally makes inventory value adjustments against the inventory reserve.
Property and Equipment	Property and equipment are stated at cost, net of accumulated depreciation and amortization. Depreciation is determined using the straight-line method over the estimated useful lives of the respective assets, generally ranging from three to seven years. Leasehold improvements are amortized on a straight-line basis over the shorter of their estimated useful lives or the related lease term. Depreciation for equipment commences once it is placed in service, and depreciation for buildings and leasehold improvements commences once they are ready for their intended use. The Company expenses maintenance and repair costs that do not extend the life of the asset as they are incurred.
Property and Equipment, Impairment	The Company evaluates the carrying amount of its property and equipment whenever events or changes in circumstances indicate that the assets may not be recoverable. An impairment loss would be recognized when estimated future cash flows expected to result from the use of an asset or asset group and its eventual disposition are less than the carrying amount of the asset or asset group.
Goodwill	Goodwill arose for the acquisition of a business in February 2014 based in Japan and was accounted for as the purchase of a business. Goodwill generated from business combinations and deemed to have indefinite lives are not subject to amortization and instead are tested for impairment at least annually in December unless certain events occur or circumstances change. Goodwill represents the excess of the purchase price over the fair value of the net assets and other identifiable intangible assets acquired. We test for goodwill impairment annually, on March 31, or earlier if events or changes in circumstances indicate goodwill might possibly be impaired. Impairment exists when the carrying value of the goodwill exceeds its implied fair value. An impairment loss would be recognized in an amount equal to that excess as a charge to operations in the consolidated statements of operations.
Intangible Assets	Intangible assets that are not considered to have an indefinite useful life are amortized over their estimated useful lives, which generally range from three to ten years. Each reporting period, the Company evaluates the estimated remaining useful lives of intangible assets and whether events or changes in circumstances warrant a revision to the remaining periods of amortization.If it is determined that the carrying values might not be recoverable based upon the existence of one or more indicators of impairment, the Company performs a test for recoverability using various methodologies, such as the income approach or cost approach, to determine the fair value of intangible assets depending upon the nature of the assets. If assets are considered to be impaired, the impairment to be recognized is measured as the amount by which the carrying amount of the assets exceeds their respective fair values.
Revenue Recognition	The Company derives its revenues from sales of high-powered GaN-based products manufactured utilizing the Company’s proprietary and patented epiwafer technology and wafer fabrication and other assembly processes, sales of GaN epiwafers for the radio frequency (“RF”) and power markets, and sales of licenses to use such patented proprietary technology, as well as enabling EPI wafer growth services and products to our strategic partners. Revenues are recognized when control of these products or licenses are transferred to the Company’s customers in an amount that reflects the consideration it expects to be entitled to in exchange for those products and licenses. Sales and other taxes the Company collects concurrent with revenue-producing activities are excluded from revenue. Incidental items that are immaterial in the context of the contract are recognized as expense. The Company does not have any significant financing components associated with its revenue contracts, as payment is received at or shortly after the point of sale. Disaggregation of Revenue from Contracts with Customers Revenue consists of perpetual licensing revenue, government contract revenue from our contract with the U.S. Navy and product sales, with applicable performance obligations satisfied at a point in time. Products are sold to distributors and end-users in various sectors such as, but not limited to, the automotive, gaming, industrial, IT, and consumer products industries. As part of the multi-element commercial arrangement executed with Nexperia on April 4, 2018 (see Note 3 - Nexperia Arrangement), the Company agreed to grant Nexperia the perpetual exclusive right to use the Company’s existing Gen-3 manufacturing process technology. License fees are received upon satisfaction of contractual milestones and recognized upon delivery of the perpetual license or transferred technology without any remaining performance obligations. The Company recognized $8.0 million of perpetual licensing revenue for the year ended March 31, 2022. No perpetual licensing revenue was recognized for the three months ended March 31, 2021. The Company recognized $5.0 million of perpetual licensing revenue for the year ended December 31, 2020. In December 2020, the Company entered into a cooperation and development agreement with Yaskawa Electric Corporation (“Yaskawa”), pursuant to which Yaskawa agreed to provide $4.0 million over approximately three years to fund development activities related to industrial power conversion applications, with an initial focus on servo motor drive applications. Yaskawa provided payments of $1.0 million and $750 thousand of this $4.0 million commitment in December 2020 and July 2021, respectively. The Company evaluated and concluded that the deliverables are the same and nature of the services to be provided to Yaskawa will be consistent over the period of approximately three years. Accordingly, with respect to the $1.8 million payment, the Company recognized $1.1 million as revenue for the year ended March 31, 2022, $333 thousand as revenue for the three months ended March 31, 2021 and $333 thousand as revenue for the year ended December 31, 2020. The Company also recorded $375 thousand as revenue for services rendered but not billed for the year ended March 31, 2022. Government contract revenues are principally generated under research and development contracts. Contract revenues are derived primarily from research contracts with agencies of the U.S. government. We believe credit risk related to accounts receivable arising from such contracts is minimal. These contracts may include cost-plus fixed fee and fixed price terms. All payments to us for work performed on contracts with agencies of the U.S. government are subject to adjustment upon audit by the Defense Contract Audit Agency. The contract’s expiration dates were initially March and June 2022, but such dates were subsequently extended to June and December 2022, respectively. The Company received new government authorized rates for billing purposes which allowed for retroactive application since inception. The cumulative impact of this rate change as of March 31, 2022 was $423 thousand, of which $(83) thousand and $505 thousand were recorded in the three months ended March 31, 2021 and year ended December 31, 2021, respectively. On February 1, 2022, the Company received new government authorized rates which allowed for retroactive application effective for the year ended December 31, 2020. The Company will use the new approved rates on a go-forward basis. Performance Obligations For performance obligations related to the sale of products, control transfers to the customer at a point in time. The Company’s principal terms of sale are free on board shipping or destination and the Company transfers control and records revenue for product sales upon shipment or delivery to the customer, respectively. For performance obligations related to the licensing of patented technology in perpetuity, control also transfers to the customer at a point in time. The Company transfers control and records revenue for licensing fees once the Company has (i) provided or otherwise makes available the patented technology to the customer and (ii) the customer is able to use and benefit from the patented technology. Variable Consideration The nature of the Company’s arrangement with Nexperia gives rise to variable consideration in the form of milestone and royalty payments. The royalties qualify for the sales and usage-based royalty exception, as the license of intellectual property is the predominant item to which the royalty relates and are recognized upon the subsequent sale occurring. The variable amounts are received upon satisfaction of contractually agreed upon development targets and sales volume.
Research and Development	The Company is a party to research grant contracts with the U.S. government for which the Company is reimbursed for specified costs incurred for its research projects. These projects include energy saving initiatives for which the U.S. government offers reimbursement funds. Such reimbursements are recorded as an offset to research and development expenses when the related qualified research and development expenses are incurred. Reimbursable costs are recognized in the same period the costs are incurred up to the limit of approved funding amounts on qualified expenses.
Stock-Based Compensation	All share-based payments, including grants of stock options, restricted stock awards (“RSAs”) and restricted stock units (“RSUs”), are measured at the fair value of the share-based awards on the grant date and recognized over their respective vesting periods, which is generally one to four years. The estimated fair value of stock options at the grant date is determined using the Black-Scholes-Merton pricing model, and the RSAs and RSUs are measured using the fair market value of the stock price at grant date. The Company recognizes the fair value of share-based payments as compensation expense for all expected-to-vest stock-based awards over the vesting period of the award using the straight-line attribution or graded vesting method provided that the amount of compensation cost recognized at any date is no less than the portion of the grant-date fair value of the award that is vested at that date. The Black-Scholes-Merton option pricing model requires inputs such as the fair value of common stock on date of grant, expected term, expected volatility, dividend yield, and risk-free interest rate. Further, the forfeiture rate also affects the amount of aggregate compensation expense. These inputs are subjective and generally require significant analysis and judgment to develop. Volatility data is obtained from a study of publicly traded industry peer companies. The forfeiture rate is derived primarily from the Company’s historical data, and the risk-free interest rate is based on the yield available on U.S. Treasury zero-coupon issues commensurate with the expected term. Management generally uses the simplified method to calculate the expected term for employee grants as the Company has limited historical exercise data or alternative information to reasonably estimate an expected term assumption. The simplified method assumes that all options will be exercised midway between the weighted average vesting date and the contractual term of the option. Stock-based compensation expense recognized in the Company’s consolidated financial statements is based on awards that are expected to vest. These expense amounts have been reduced by using an estimated forfeiture rate. Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates. The Company evaluates the assumptions used to estimate forfeitures annually in connection with the recognition of stock-based compensation expense. Stock-based compensation expense is determined based on the fair value of the Company’s common stock as determined by the Board of Directors and assumptions such as volatility, expected term, risk-free interest rates, and other factors. Changes in the deemed fair value of the common stock, the underlying assumptions in the calculations, the number of options granted or the terms of such options, the expected forfeiture rate, the treatment of tax benefits and other changes may result in significant differences in the amounts or timing of the compensation expense recognized. The assumptions and estimates are made as follows: •Expected Volatility - The Company utilizes the historical volatility of representative public companies to determine its expected volatility, as the trading history of the Company’s common stock is limited. •Estimated Forfeitures - The Company adopted ASU 2016-09, Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting and has elected to account for forfeitures as they occur and therefore, stock-based compensation expense has been calculated based on actual forfeitures in the statements of operations, rather than our previous approach which was net of estimated forfeitures. The net cumulative effect of this change was not material. •Expected Dividend Yield - The Company has not issued any common stock dividends; therefore, a dividend yield of zero was used. •Risk-Free Interest Rate - The Company bases the risk-free interest rate used in the Black-Scholes-Merton option pricing model on the implied yield currently available on United States Treasury zero-coupon issues with an equivalent expected term. •Expected Term - The expected term of stock options represents the period that the Company’s stock options are expected to be outstanding. The Company generally uses the simplified method to calculate the expected term for employee grants.
Income (Loss) Per Share	Basic income (loss) per share is calculated by dividing net income (loss) applicable to common stockholders by the weighted average number of common shares outstanding during the period. Diluted income (loss) per share is calculated by dividing the net loss attributable to common stockholders by the sum of the weighted average number of common shares outstanding plus potential dilutive common shares outstanding during the period. Potential dilutive securities, comprised of stock warrants, restricted stock units and stock options, are not reflected in diluted income (loss) per share because such shares are anti–dilutive. Dilutive impact of potential common shares resulting from common stock equivalents is determined by applying the treasury stock method.
Fair Value Measurement	Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The carrying values of the Company’s financial instruments such as cash equivalents, accounts receivable, revolving credit facility, accounts payable and accrued liabilities approximate fair values due to the short-term nature of these items.
Income Taxes	The Company accounts for income taxes in accordance with Accounting Standards Codification (“ASC”) 740, Income Taxes (“ASC 740”). ASC 740 prescribes the use of the liability method. Deferred tax assets and liabilities are determined based on the difference between the financial statement carrying amounts and the tax basis of assets and liabilities and are measured using the enacted statutory tax rates in effect at the balance sheet date. The Company records a valuation allowance to reduce its deferred tax assets when uncertainty regarding their realizability exists.
Equity Method Investments	The Company uses the equity method to account for investments in entities that it does not control, but in which it has the ability to exercise significant influence over operating and financial policies. The Company's proportionate share of the net income or loss of these companies is included in consolidated net loss. Judgments regarding the level of influence over each equity method investment include consideration of key factors such as the Company's ownership interest, representation on the board of directors or other management body and participation in policy-making decisions.
Segment Reporting	The Company’s operations and its financial performance is evaluated on a consolidated basis by the chief operating decision maker. The Company’s chief operating decision maker is the Parent’s Chief Executive Officer. Accordingly, the Company considers all of its operations to be aggregated in one reportable operating segment. For the year ended March 31, 2022, total revenue was $24.1 million, of which $23.4 million was from U.S. operations and $698 thousand was from Japan operations. For the three months ended March 31, 2021, total revenue was $2.4 million, of which $2.0 million was from U.S. operations and $449 thousand was from Japan operations. For the year ended December 31, 2020, total revenue was $11.4 million, of which $10.7 million was from U.S. operations and $713 thousand was from Japan operations.
Recently Issued Accounting Standards under Evaluation	Recently Issued Accounting Standards under Evaluation Debt - In August 2020, the FASB issued ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity, to address the complexity in accounting for certain financial instruments with characteristics of liabilities and equity. Amongst other provisions, the amendments in this ASU significantly change the guidance on the issuer’s accounting for convertible instruments and the guidance on the derivative scope exception for contracts in an entity’s own equity such that fewer conversion features will require separate recognition, and fewer freestanding instruments, like warrants, will require liability treatment. Refer to our white paper, Accounting simplifications for convertible instruments and warrants, for additional information. ASU 2020-06 is effective for fiscal years beginning after December 15, 2021. The Company is currently evaluating the impact of this new standard on its consolidated financial statements and the adoption is not expected to have a significant impact on the consolidated financial statements. Leases - In June 2020, the FASB issued ASU 2020-05, which amends the effective dates of the FASB’s standards on leasing (ASC 842) to give immediate relief to certain entities as a result of the widespread adverse economic effects and business disruptions caused by the COVID-19 pandemic. In February 2016, the FASB issued ASU 2016-02, Leases, which, for operating leases, requires the lessee to recognize a right-of-use asset and a lease liability, initially measured at the present value of the lease payments, on its balance sheet. The guidance also requires a lessee to recognize single lease costs, calculated so that the cost of the lease is allocated over the lease term, on a generally straight-line basis. The leasing standard’s effective dates were the fiscal year beginning after December 15, 2019 as originally issued (ASU 2016-02) and the fiscal year beginning after December 15, 2020 as amended by ASU 2019-10. As amended by ASU 2020-05, the leasing standard’s effective date is now the fiscal year beginning after December 15, 2021. The Company is currently evaluating the impact of this new standard on its consolidated financial statements and the adoption is not expected to have a significant impact on the consolidated financial statements. Financial Instruments - FASB ASU 2020-03, Codification Improvements to Financial Instruments, makes clear the determination of the contractual life of a net investment in leases in estimating expected credit losses under ASC 326, Financial Instruments – Credit Losses. In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”). The standard changes the methodology for measuring credit losses on financial instruments and the timing of when such losses are recorded. ASU 2016-13 is effective for the Company in 2023. Early adoption is permitted. The Company is currently evaluating the impact of this new standard on its consolidated financial statements and the adoption is not expected to have a significant impact on the consolidated financial statements. Income Tax - In December 2019, the FASB issued ASU 2019-12, which modifies ASC 740 to simplify the accounting for income taxes. The ASU’s amendments are based on changes that were suggested by stakeholders as part of the FASB’s simplification initiative (i.e., the FASB’s effort to reduce the complexity of accounting standards while maintaining or enhancing the helpfulness of information provided to financial statement users). ASU 2019-12 is effective for fiscal years beginning after December 15, 2022. The Company is currently evaluating the impact of this new standard on its consolidated financial statements and the adoption is not expected to have a significant impact on the consolidated financial statements.

Concentration of Credit Risk and Significant Customers (Tables)

12 Months Ended

Mar. 31, 2022

Risks and Uncertainties [Abstract]

Schedules of concentration of risk, by risk factor

Total revenues, by percentage, from individual customers representing 10% or more of total revenues in the respective periods were as follows:

For the Year Ended March 31, 2022

For the Three Month Transition Period Ended March 31, 2021

For the Year Ended December 31, 2020

Customer A

42.4%

27.3%

59.6%

Customer B

16.1%

31.2%

29.2%

Customer C

19.6%

Customer D

* Less than 10% of total

Accounts receivable, by percentage, from individual customers representing 10% or more of accounts receivable are set forth in the following table:


	As of March 31,
	2022	2021
Customer A	20.1%	31.1%
Customer B	19.4%	33.9%
Customer C	38.8%	*
Customer D	*	10.0%

* Less than 10% of total

Inventory (Tables)

12 Months Ended

Mar. 31, 2022

Inventory Disclosure [Abstract]

Schedule of inventory

Inventory consists of the following as of the dates presented (in thousands):


	March 31, 2022		March 31, 2021
Raw materials	$	2,412	$	626
Work in process	1,865		1,054
Finished goods	2,053		543
Total	$	6,330	$	2,223

Property and Equipment (Tables)

12 Months Ended

Mar. 31, 2022

Property, Plant and Equipment [Abstract]

Schedule of property and equipment

Property and equipment as of the dates presented consists of the following (in thousands except years):


	March 31, 2022		March 31, 2021		Estimated Useful Life (in years)
Machinery and equipment	$	15,255	$	14,748	5
Computer equipment and software	872		836		3
Furniture and fixtures	179		185		7
Leasehold improvements (1)	4,950		4,959		7
Construction in progress	384		137
Property and equipment, gross	21,640		20,865
Less: accumulated depreciation and amortization	(19,991)		(19,505)
Property and equipment, net	$	1,649	$	1,360

(1) Leasehold improvements are amortized on a straight-line basis over the shorter of their estimated useful lives or the related remaining lease term.

Intangible Assets (Tables)

12 Months Ended

Mar. 31, 2022

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of carrying value of intangible assets

The carrying values of intangible assets as of the dates presented, respectively, consists of the following (in thousands except years):


	March 31, 2022
	Gross		Accumulated Amortization		Foreign Exchange Rate Changes		Net		Estimated Useful Life (in years)
Patents	$	2,963	$	(2,346)	$	—	$	617	10
Developed technology - 150V	560		(517)		(43)		—		6
Developed technology - 600V	1,701		(1,570)		(131)		—		6
Total	$	5,224	$	(4,433)	$	(174)	$	617

	March 31, 2021
	Gross		Accumulated Amortization		Foreign Exchange Rate Changes		Net		Estimated Useful Life (in years)
Patents	$	2,963	$	(2,049)	$	—	$	914	10
Developed technology - 150V	560		(517)		(43)		—		6
Developed technology - 600V	1,701		(1,570)		(131)		—		6
Total	$	5,224	$	(4,136)	$	(174)	$	914

Schedule of estimated future amortization expenses related to intangible assets

Estimated future amortization expenses related to intangible assets as of March 31, 2022 were as follows (in thousands):


Year Ending March 31,
2023	$	296
2024	296
2025	25
Total	$	617

Investment in Joint Venture (Tables)

12 Months Ended

Mar. 31, 2022

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of investment activities in AFSW

The Company’s investment activities in GaNovation and AFSW for the periods presented are summarized below (in thousands):


AFSW (Joint Venture Between the Company and FSL)
January 1, 2020	$	(1,688)
Investment	7,348
Loss	(6,836)
Effect of exchange rate change	(290)
December 31, 2020	(1,466)
Investment	968
Loss	(1,468)
Effect of exchange rate change	100
March 31, 2021	(1,866)
Investment	2,490
Loss	(2,078)
Gain	1,455
Effect of exchange rate change	(1)
July 31, 2021	$	—

GaNovation (Joint Venture Between the Company and JCP)
August 1, 2021	$	—
Investment	2,036
Loss	(1,893)
Effect of exchange rate change	—
March 31, 2022	$	143

Summarized unaudited financial information of GaNovation and AFSW for the periods indicated are as follows (in thousands):


					GaNovation		AFSW
					March 31, 2022		March 31, 2021
Current assets					4,259		$	932
Long-term assets					3,690		$	5,330
Other current liabilities					3,799		$	2,200
Due to controlling owner					(1)		$	22,354
Due to Transphorm					—		$	13,179
Net surplus (deficit)					4,151		$	(31,471)

	GaNovation		AFSW
	For the Eight Months Ended March 31, 2022		For the Four Months Ended July 31, 2021		For the Three Month Transition Period Ended March 31, 2021		For the Year Ended December 31, 2020
Sales	$	6,933	$	2,176	$	842	$	2,976
Gross loss	$	(6,168)	$	(3,191)	$	(2,425)	$	(11,411)
Net loss	$	(7,707)	$	(4,260)	$	(2,995)	$	(13,952)

- Definition

Tabular disclosure of the significant judgments and assumptions made in determining whether a variable interest (as defined) held by the entity requires the variable interest entity (VIE) (as defined) to be consolidated and (or) disclose information about its involvement with the VIE, individually or in aggregate (as applicable); the nature of restrictions, if any, on the consolidated VIE's assets and on the settlement of its liabilities reported by an entity in its statement of financial position, including the carrying amounts of such assets and liabilities; the nature of, and changes in, the risks associated with involvement in the VIE; how involvement with the VIE affects the entity's financial position, financial performance, and cash flows; the lack of recourse if creditors (or beneficial interest holders) of the consolidated VIE have no recourse to the general credit of the primary beneficiary (if applicable); the terms of arrangements, giving consideration to both explicit arrangements and implicit variable interests, if any, that could require the entity to provide financial support to the VIE, including events or circumstances that could expose the entity to a loss; the methodology used by the entity for determining whether or not it is the primary beneficiary of the variable interest entity; the significant factors considered and judgments made in determining that the power to direct the activities of a VIE that most significantly impact the VIE's economic performance are shared (as defined); the carrying amounts and classification of assets and liabilities of the VIE included in the statement of financial position; the entity's maximum exposure to loss, if any, as a result of its involvement with the VIE, including how the maximum exposure is determined and significant sources of the entity's exposure to the VIE; a comparison of the carrying amounts of the assets and liabilities and the entity's maximum exposure to loss; information about any liquidity arrangements, guarantees, and (or) other commitments by third parties that may affect the fair value or risk of the entity's variable interest in the VIE; whether or not the entity has provided financial support or other support (explicitly or implicitly) to the VIE that it was not previously contractually required to provide or whether the entity intends to provide that support, including the type and amount of the support and the primary reasons for providing the support; and supplemental information the entity determines necessary to provide.

+ References + Details

Debts (Tables)

12 Months Ended

Mar. 31, 2022

Debt Disclosure [Abstract]

Schedule of promissory note obligation

The Company’s stated value of promissory note obligation as of the dates presented consists of the following (in thousands):


	Interest Rate	Due Date	March 31, 2022		March 31, 2021
Yaskawa Note	1.00%	September 2022	$	—	$	15,523

Schedule of fair value option

As of the dates presented, the Company determined the fair value for the note, as compared to the face value, including accrued interest, as follows (in thousands):


	March 31, 2022		March 31, 2021
Yaskawa Note	$	—	$	16,128

Schedule of maturities of long-term debt

As of March 31, 2022, the scheduled maturity, including accrued interest, of the Company’s borrowings under the Tranche C Loans was as follows (in thousands):


Year Ending March 31,
2023	$	180
2024	12,000
Total	$	12,180

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

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+ Details

Commitments and Contingencies (Tables)

12 Months Ended

Mar. 31, 2022

Commitments and Contingencies Disclosure [Abstract]

Schedule of future minimum operating lease commitments

As of March 31, 2022, future minimum operating lease commitments were as follows (in thousands):


Year Ending March 31,
2023	$	681
2024	647
2025	156
Total	$	1,484

Stockholders' Equity (Deficit) (Tables)

12 Months Ended

Mar. 31, 2022

Equity [Abstract]

Schedule of convertible preferred stock by class

The Company has reserved shares of common stock for future issuance as of date presented as follows:


			March 31, 2022
Equity incentive plans			6,707,843
Common stock warrants			2,657,298
Total			9,365,141

Schedule of stockholders' equity note, warrants or rights

The following warrants to purchase common stock were outstanding as of March 31, 2022:


Number of Shares	Exercise Price		Expiration Date
6,046	$	34.74	5 years after an initial public offering of the Company
3,369	$	54.41	5 years after an initial public offering of the Company
45,000	$	3.30	December 23, 2025
209,000	$	6.00	August 13, 2024
650,000	$	6.00	October 4, 2024
958,334	$	6.00	November 5, 2024
416,667	$	6.00	November 9, 2024
348,649	$	9.25	December 7, 2024
20,233	$	8.48	December 10, 2025
2,657,298

- Definition

Tabular disclosure of an entity's stock, including par or stated value per share, number and dollar amount of share subscriptions, shares authorized, shares issued, shares outstanding, number and dollar amount of shares held in an employee trust, dividend per share, total dividends, share conversion features, par value plus additional paid in capital, the value of treasury stock and other information necessary to a fair presentation, and EPS information. Stock by class includes common, convertible, and preferred stocks which are not redeemable or redeemable solely at the option of the issuer. Includes preferred stock with redemption features that are solely within the control of the issuer and mandatorily redeemable stock if redemption is required to occur only upon liquidation or termination of the reporting entity. If more than one issue is outstanding, state the title of each issue and the corresponding dollar amount; dollar amount of any shares subscribed but unissued and the deduction of subscriptions receivable there from; number of shares authorized, issued, and outstanding.

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+ Details

Stock-Based Compensation (Tables)

12 Months Ended

Mar. 31, 2022

Share-based Payment Arrangement [Abstract]

Schedule of stock option activity

The following table summarizes stock option activity and related information for the periods presented:


	Number of Options	Weighted Average Exercise Price per Share		Weighted Average Remaining Contractual Term (in Years)	Aggregate Intrinsic Value (1) (in thousands)
Outstanding at January 1, 2020	2,473,198	$	4.67	6.84	$	—
Options granted	—	$	—
Options exercised	(6,821)	$	3.78
Options canceled	(146,059)	$	5.88
Outstanding at December 31, 2020	2,320,318	$	4.67	5.92	$	—
Exercisable at December 31, 2020	2,267,154	$	4.70	5.86	$	—

Outstanding at January 1, 2021	2,320,318	$	4.67	5.92	$	—
Options granted	223,638	$	6.37
Options exercised	(500)	$	3.14
Options canceled	(331)	$	9.29
Outstanding at March 31, 2021	2,543,125	$	4.82	6.05	$	—
Exercisable at March 31, 2021	2,283,243	$	4.70	5.65	$	—

Outstanding at April 1, 2021	2,543,125	$	4.82	6.05	$	—
Options granted	528,077	$	6.31
Options exercised	(52,799)	$	4.19
Options canceled	(139,395)	$	9.52
Outstanding at March 31, 2022	2,879,008	$	4.88	6.02	$	6,747
Exercisable at March 31, 2022	2,206,259	$	4.44	4.99	$	5,984

Schedule of valuation assumptions

The assumptions used to value options granted to employees during the periods presented was as follows:


	Year Ended March 31, 2022	Three Month Transition Period Ended March 31, 2021
Weighted average expected life (in years)	5.87	5.23
Risk-free interest rate	1.08% - 1.32%	0.78% - 1.73%
Expected volatility	42.5% - 43.8%	43.1% - 44.3%
Grant date fair market value	$6.34	$3.75
Grant date fair value	$1.94 - $3.32	$0.94 - $1.65
Dividend yield	—%	—%

Schedule of unvested restricted stock units

The following table summarizes RSA activity and related information for the periods presented:


	Number of Shares	Weighted-Average Grant Date Fair Value Per Share
January 1, 2020	—	$	—
Granted	135,501	$	3.91
Vested	(98,450)	$	3.88
December 31, 2020	37,051	$	4.00
Granted	—	$	—
Vested	(37,051)	$	4.00
March 31, 2021	—	$	—
Granted	—	$	—
Vested	—	$	—
March 31, 2022	—	$	—

The following table summarizes RSU activity and related information for the periods presented:


	Number of Shares	Weighted-Average Grant Date Fair Value Per Share
January 1, 2020	—	$	—
Granted	816,180	$	4.00
Vested	(4,000)	$	4.00
Canceled	(6,855)	$	4.00
December 31, 2020	805,325	$	4.00
Granted	137,452	$	3.75
Vested	(3,000)	$	3.75
Canceled	(4,380)	$	4.00
March 31, 2021	935,397	$	3.96
Granted	342,640	$	6.31
Vested	(305,982)	$	3.98
Canceled	(17,280)	$	3.98
March 31, 2022	954,775	$	4.61

Stock-based compensation expense

The accompanying consolidated statement of operations and comprehensive loss includes stock-based compensation expense for the periods presented as follows (in thousands):


	Year Ended March 31, 2022		Three Month Transition Period Ended March 31, 2021		Year Ended December 31, 2020
Cost of revenue	$	161	$	39	$	93
Research and development	552		115		306
Sales and marketing	190		33		68
General and administrative	1,711		326		1,058
Total	$	2,614	$	513	$	1,525

Unrecognized stock-based compensation

Unrecognized stock-based compensation expense as of dates presented was as follows (in thousands):


	March 31, 2022			March 31, 2021
	Unrecognized Expense		Average Expected Recognition Period (in years)	Unrecognized Expense		Average Expected Recognition Period (in years)
Stock options	$	1,413	2.11	$	280	5.06
Restricted stock	2,576		1.57	2,738		1.76
Total	$	3,989	1.76	$	3,018	2.07

Fair Value Measurements (Tables)

12 Months Ended

Mar. 31, 2022

Fair Value Disclosures [Abstract]

Liabilities measured at fair value by level

The following table summarizes the Company’s liabilities measured at fair value as of the dates presented, by level within the fair value hierarchy (in thousands):


	Level 1		Level 2		Level 3
March 31, 2022
Promissory note	$	—	$	—	$	—
March 31, 2021
Promissory note	$	—	$	—	$	16,128

Changes in fair value of promissory notes

The following table includes the changes in fair value of the promissory note which are Level 3 on the fair value hierarchy (in thousands):


January 1, 2020	$	16,169
Interest expense accrued	150
Decrease in fair value	(927)
December 31, 2020	15,392
Interest expense accrued	37
Increase in fair value	699
March 31, 2021	16,128
Interest expense accrued	77
Decrease in fair value	(605)
Conversion	(15,600)
March 31, 2022	$	—

Fair value of promissory note

The following table summarizes assumptions used for fair value of promissory note as of the dates presented:


			March 31, 2021
Stock price			$3.75
Time			1.5 years
Risk-free rate			0.12%
Volatility			50.6%

Income Taxes (Tables)

12 Months Ended

Mar. 31, 2022

Income Tax Disclosure [Abstract]

Schedule of significant components of deferred tax assets and liabilities

Significant components of the Company’s deferred tax assets and deferred tax liabilities as of the dates presented as follows (in thousands):


	March 31, 2022		March 31, 2021
Deferred tax assets:
Net operating loss carryforwards	$	49,715	$	47,424
Tax credits	6,171		5,444
California capitalized research and development	40		72
Others, net	564		581
Total deferred tax assets	56,490		53,521
Valuation allowance	(56,550)		(53,481)
Deferred tax asset, net of valuation allowance	(60)		40
Deferred tax liabilities:
Fixed assets	60		(40)
Total deferred tax liabilities	60		(40)
Net deferred tax assets	$	—	$	—

Schedule of reconciliation between the federal statutory rate and the effective tax rate

Reconciliation between federal statutory tax rate and the effective tax rate is shown in the following table for the periods presented:


	Year Ended March 31, 2022		Three Month Transition Period Ended March 31, 2021		Year Ended December 31, 2020
Federal statutory income tax rate	21.00	%	21.00	%	21.00	%
Research and development credit	7.10	%	2.73	%	4.06	%
Nondeductible expense	1.80	%	(2.43)	%	0.64	%
Loss in joint venture	(1.87)	%	(6.76)	%	(11.70)	%
Foreign income tax rate difference	1.39	%	2.45	%	4.10	%
Others, net	(0.40)	%	0.85	%	(2.08)	%
Valuation allowance	(29.02)	%	(17.84)	%	(16.02)	%
Effective tax rate	—	%	—	%	—	%

Business and Basis of Presentation (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended	12 Months Ended
	Feb. 12, 2020	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2020	Dec. 07, 2021	Nov. 09, 2021	Oct. 04, 2021	Aug. 13, 2021	Dec. 23, 2020	Feb. 27, 2020	Feb. 11, 2020	Dec. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Merger conversion rate (in shares)	0.08289152527
Common stock, shares issued (in shares)	4,171,571	40,531,996	53,379,307								50,325,662
Common stock, forfeited and cancelled (in shares)	682,699
Shares issued under company plans (in shares)	2,461,923	2,543,125	2,879,008	2,320,318								2,473,198
Number of shares (in shares)	15,461		2,657,298								186,535
Conversion price per share on convertible note payable (in dollars per share)	$ 5.12						$ 5.00
Number of common stock shares converted per preferred share (in shares)							3,120,000
Net cash used in operating activities		$ (4,933)	$ (19,736)	$ (14,115)
Proceeds from issuance of common stock		1,000	50,900	36,520
Series 1 Preferred Stock
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Common stock, shares issued (in shares)	12,433,953
Convertible preferred stock, shares issued (in shares)	51,680,254										51,680,254
Convertible preferred stock, shares outstanding (in shares)	51,680,254										51,680,254
Conversion of preferred shares in connection with the Reverse Merger (in shares)	12,433,953
Series 2 Preferred Stock
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Common stock, shares issued (in shares)	7,499,996
Convertible preferred stock, shares issued (in shares)	38,760,190										38,760,190
Convertible preferred stock, shares outstanding (in shares)	38,760,190										38,760,190
Conversion of stock (in shares)	7,499,996
Series 3 Preferred Stock
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Common stock, shares issued (in shares)	4,000,000
Convertible preferred stock, shares issued (in shares)	31,850,304										31,850,304
Convertible preferred stock, shares outstanding (in shares)	31,850,304										31,850,304
Conversion of stock (in shares)	4,000,000
Yaskawa
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Conversion price per share on convertible note payable (in dollars per share)	$ 5.12						$ 5.00
Yaskawa Note
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accrued interest on promissory note		$ 523	0	$ 486
Yaskawa Note \| Yaskawa
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Principal and unpaid interest of convertible note							$ 15,600
Principal amount of long term loan facility							15,000
Accrued interest on promissory note							$ 600
Number of common stock shares converted per preferred share (in shares)							3,120,000
Transphorm Technology 2007 Stock Plan and 2015 Equity Incentive Plan
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Shares issued under company plans (in shares)	29,703,285
Former Holders of Tranphorm Technology's Common Stock
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Common stock, shares issued (in shares)	4,171,571
Conversion of preferred shares in connection with the Reverse Merger (in shares)	28,105,520
Private Placement
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Price per share (in dollars per share)		$ 4.00			$ 7.71	$ 5.00		$ 5.00	$ 3.00	$ 4.00
Proceeds from issuance of common stock			$ 50,900
Common Stock
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Price per share (in dollars per share)	$ 4.00
Conversion of preferred shares in connection with the Reverse Merger (in shares)			3,120,000	23,933,949

Summary of Significant Accounting Policies (Details)		1 Months Ended			3 Months Ended	12 Months Ended
Summary of Significant Accounting Policies (Details)	Jul. 16, 2021 USD ($)	Dec. 31, 2021 USD ($)	Jul. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Mar. 31, 2021 USD ($) shares	Mar. 31, 2022 USD ($) segment shares	Dec. 31, 2020 USD ($) shares
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Restricted cash						$ 575,000
Restricted cash in current asset					$ 0	500,000
Cash and cash equivalents included in other assets					9,500,000	33,435,000
Provision for doubtful accounts					(48,000)	0	$ 110,000
Recovery from doubtful accounts					48,000
Goodwill impairment charges					0	0	0
Impairment of intangible assets					0	0	0
Revenue from product and license fees					2,425,000	$ 24,050,000	11,371,000
Term of cooperation and development agreement.				3 years		3 years
Revenue for services rendered					505,000	$ 346,000
Cumulative effect of government rate change		$ 505,000			(83,000)	423,000
Grant reimbursement					$ 42,000	$ 345,000	$ 426,000
Number of anti-dilutive shares (in shares) \| shares					3,637,937	6,491,081	3,285,058
Number of reportable segments \| segment						1
Stock options
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of anti-dilutive shares (in shares) \| shares					2,543,125	2,879,008	2,320,318
Restricted Stock Awards (RSA)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of anti-dilutive shares (in shares) \| shares					935,397	954,775	805,325
Warrant
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of anti-dilutive shares (in shares) \| shares					159,415	2,657,298	159,415
Yaskawa
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Letter of intent for development activities				$ 4,000,000
Proceeds from collaborators			$ 750,000	$ 1,000,000		$ 1,800,000
Revenue recognized for collaboration development activities					$ 333,000	1,100,000	$ 333,000
Revenue for services rendered						375,000
License and Service
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue from product and license fees	$ 8,000,000				0	$ 8,000,000	5,000,000
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property and equipment, estimated useful life						3 years
Estimated useful life of intangible assets (in years)						3 years
Award vesting period						1 year
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property and equipment, estimated useful life						7 years
Estimated useful life of intangible assets (in years)						10 years
Award vesting period						4 years
Japan
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cash and cash equivalents included in other assets					$ 444,000	$ 66,000
Percentage of cash and cash equivalents in foreign subsidiary					4.70%	0.20%
Revenue from product and license fees					$ 449,000	$ 698,000	713,000
U.S.
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue from product and license fees					$ 2,000,000	23,400,000	$ 10,700,000
Other Assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Restricted cash						$ 75,000

Nexperia Arrangement (Details) - USD ($)				1 Months Ended						2 Months Ended	3 Months Ended	12 Months Ended
Nexperia Arrangement (Details) - USD ($)	Jul. 16, 2021	Jun. 29, 2020	Apr. 04, 2018	Jun. 30, 2020	Dec. 31, 2019	Oct. 31, 2019	Apr. 30, 2019	Jan. 31, 2019	Oct. 31, 2018	Jul. 31, 2019	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2021	May 18, 2021	May 17, 2021	Mar. 01, 2021	Mar. 31, 2019
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
License fees			$ 9,000,000	$ 5,000,000		$ 3,000,000	$ 3,000,000		$ 3,000,000					$ 9,000,000
Reduction of debt											$ 0	$ 0	$ 50,000
Supply agreement renewal term												1 year
Revenue from product and license fees											2,425,000	$ 24,050,000	11,371,000
Nexperia
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Term after notification of epiwafer qualification of a second source												2 years
License and Service
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue from product and license fees	$ 8,000,000										$ 0	$ 8,000,000	$ 5,000,000
Tranche A Loan
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Long-term loan facility			5,000,000
Reduction of debt				$ 5,000,000
Proceeds from issuance of debt								$ 5,000,000
Repayment of Nexperia debt		$ 5,000,000
Tranche B Loan
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Long-term loan facility			10,000,000							$ 8,000,000						$ 8,000,000			$ 8,000,000	$ 8,000,000
Proceeds from issuance of debt										$ 8,000,000
Repayment of Nexperia debt	8,000,000
Tranche C Loan
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revolving loan			10,000,000																10,000,000
Proceeds from issuance of debt															$ 10,000,000
Tranche B-1 Loan
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Long-term loan facility					$ 2,000,000									$ 2,000,000			$ 2,000,000	$ 2,000,000	2,000,000	$ 2,000,000
Proceeds from issuance of debt					$ 2,000,000
Repayment of Nexperia debt	$ 8,000,000
Tranche B and Tranche B-1 loans
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Long-term loan facility																			$ 10,000,000
Series 3 Preferred Stock
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Issuance of preferred stock			$ 16,000,000

Concentration of Credit Risk and Significant Customers (Details) - Customer Concentration Risk	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2020
Revenue \| Customer A
Concentration Risk [Line Items]
Percentage of revenue or accounts receivable	27.30%	42.40%		59.60%
Revenue \| Customer B
Concentration Risk [Line Items]
Percentage of revenue or accounts receivable	31.20%	16.10%		29.20%
Revenue \| Customer C
Concentration Risk [Line Items]
Percentage of revenue or accounts receivable		19.60%
Accounts Receivable \| Customer A
Concentration Risk [Line Items]
Percentage of revenue or accounts receivable		20.10%	31.10%
Accounts Receivable \| Customer B
Concentration Risk [Line Items]
Percentage of revenue or accounts receivable		19.40%	33.90%
Accounts Receivable \| Customer C
Concentration Risk [Line Items]
Percentage of revenue or accounts receivable		38.80%
Accounts Receivable \| Customer D
Concentration Risk [Line Items]
Percentage of revenue or accounts receivable			10.00%

Inventory (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2020
Inventory Disclosure [Abstract]
Raw materials	$ 626	$ 2,412
Work in process	1,054	1,865
Finished goods	543	2,053
Total	2,223	6,330
Inventory write-off	$ 7	$ 196	$ 435

Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 20,865	$ 21,640
Less: accumulated depreciation and amortization	(19,505)	(19,991)
Property and equipment, net	1,360	1,649
Depreciation and amortization related to property, plant, and equipment	123	546	$ 509
Gain on sale of equipment	40	0	$ 0
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	14,748	$ 15,255
Estimated Useful Life (in years)		5 years
Computer equipment and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	836	$ 872
Estimated Useful Life (in years)		3 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	185	$ 179
Estimated Useful Life (in years)		7 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	4,959	$ 4,950
Estimated Useful Life (in years)		7 years
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 137	$ 384

Intangible Assets - Finite-lived intangible assets (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross	$ 5,224	$ 5,224	$ 5,224
Accumulated Amortization	(4,136)	(4,433)	(4,136)
Foreign Exchange Rate Changes	(174)	(174)	(174)
Total	914	617	914
Amortization expense	74	297		$ 326
Patents
Finite-Lived Intangible Assets [Line Items]
Gross	2,963	2,963	2,963
Accumulated Amortization	(2,049)	(2,346)	(2,049)
Foreign Exchange Rate Changes	0	0	0
Total	914	$ 617	$ 914
Estimated Useful Life (in years)		10 years	10 years
Developed Technology - 150V
Finite-Lived Intangible Assets [Line Items]
Gross	560	$ 560	$ 560
Accumulated Amortization	(517)	(517)	(517)
Foreign Exchange Rate Changes	(43)	(43)	(43)
Total	0	$ 0	$ 0
Estimated Useful Life (in years)		6 years	6 years
Developed Technology - 600V
Finite-Lived Intangible Assets [Line Items]
Gross	1,701	$ 1,701	$ 1,701
Accumulated Amortization	(1,570)	(1,570)	(1,570)
Foreign Exchange Rate Changes	(131)	(131)	(131)
Total	$ 0	$ 0	$ 0
Estimated Useful Life (in years)		6 years	6 years

Intangible Assets - Estimated future amortization expense (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Mar. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
2023	$ 296
2024	296
2025	25
Total	$ 617	$ 914

Investment in Joint Venture - Narrative (Details) $ in Thousands		3 Months Ended	4 Months Ended	8 Months Ended	12 Months Ended
	Aug. 01, 2021 JPY (¥)	Mar. 31, 2021 USD ($)	Jul. 31, 2021 USD ($)	Mar. 31, 2022 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2020 USD ($)	Aug. 01, 2021 USD ($)	Apr. 01, 2020	Dec. 31, 2019 USD ($)
Variable Interest Entity [Line Items]
Term of maximum funding obligations or investment	3 years
JCP Capital Management
Variable Interest Entity [Line Items]
Term of maximum funding obligations or investment	3 years
Aizu Fujitsu Semiconductor Wafer Solution Limited (AFSW) \| GaNovation
Variable Interest Entity [Line Items]
Percentage of voting interest acquired							100.00%
Joint Venture Company In Singapore
Variable Interest Entity [Line Items]
Ownership percentage						75.00%
Fujitsu Semiconductor Limited
Variable Interest Entity [Line Items]
Purchase of additional interest								51.00%
Aizu Fajitsu Semiconductor Wafer Solution Limited
Variable Interest Entity [Line Items]
Ownership percentage in entity			49.00%
Gain on termination of JVA and settlement of obligation					$ 1,500
Additional financial support provided to investment		$ 968	$ 2,490	$ 2,036		$ 7,348
Unfunded commitment		$ (1,866)	$ 0	$ 143	$ 143	$ (1,466)			$ (1,688)
Maximum funding obligation or investments of reporting entity							$ 12,000
Aizu Fajitsu Semiconductor Wafer Solution Limited \| April 1, 2022 through March 31, 2023
Variable Interest Entity [Line Items]
Percentage of funding obligations and losses				25.00%	25.00%
Aizu Fajitsu Semiconductor Wafer Solution Limited \| April 1, 2023 through March 31, 2024
Variable Interest Entity [Line Items]
Percentage of funding obligations and losses				32.50%	32.50%
Aizu Fajitsu Semiconductor Wafer Solution Limited \| GaNovation
Variable Interest Entity [Line Items]
Additional financial support provided to investment					$ 2,000
Aizu Fajitsu Semiconductor Wafer Solution Limited \| Aizu Fujitsu Semiconductor Wafer Solution Limited (AFSW)
Variable Interest Entity [Line Items]
Additional financial support provided to investment					$ 2,500
Aizu Fajitsu Semiconductor Wafer Solution Limited \| GaNovation
Variable Interest Entity [Line Items]
Ownership percentage in entity	25.00%
Payment for acquisition \| ¥	¥ 1
Aizu Fajitsu Semiconductor Wafer Solution Limited \| Aizu Fujitsu Semiconductor Wafer Solution Limited (AFSW) \| GaNovation
Variable Interest Entity [Line Items]
Percentage of ownership acquired	49.00%
Variable Interest Entity, Primary Beneficiary \| JCP Capital Management
Variable Interest Entity [Line Items]
Maximum funding obligation or investments of primary beneficiary							$ 35,000
Variable Interest Entity, Primary Beneficiary \| JCP Capital Management \| April 1, 2022 through March 31, 2023
Variable Interest Entity [Line Items]
Percentage of funding obligations and losses				75.00%	75.00%
Variable Interest Entity, Primary Beneficiary \| JCP Capital Management \| April 1, 2023 through March 31, 2024
Variable Interest Entity [Line Items]
Percentage of funding obligations and losses				67.50%	67.50%

Investment in Joint Venture - Income statement information (Details) - Aizu Fajitsu Semiconductor Wafer Solution Limited - USD ($) $ in Thousands	3 Months Ended	4 Months Ended	8 Months Ended	12 Months Ended
	Mar. 31, 2021	Jul. 31, 2021	Mar. 31, 2022	Mar. 31, 2022	Dec. 31, 2020
Summary of Variable Interest Entities [Roll Forward]
Balance at the beginning	$ (1,466)	$ (1,866)	$ 0	$ (1,866)	$ (1,688)
Investment	968	2,490	2,036		7,348
Loss	(1,468)	(2,078)	(1,893)		(6,836)
Gain		1,455
Effect of exchange rate change	100	(1)	0		(290)
Balance at the end	$ (1,866)	$ 0	$ 143	$ 143	$ (1,466)

Investment in Joint Venture - Summarized financial information (Details) - USD ($) $ in Thousands	3 Months Ended	4 Months Ended	8 Months Ended	12 Months Ended
	Mar. 31, 2021	Jul. 31, 2021	Mar. 31, 2022	Mar. 31, 2022	Dec. 31, 2020
Variable Interest Entity [Line Items]
Current assets	$ 14,294		$ 44,794	$ 44,794
Other current liabilities	1,866		0	0
Variable Interest Entity, Measure of Activity [Abstract]
Gross loss	637			11,520	$ 4,689
Aizu Fajitsu Semiconductor Wafer Solution Limited
Variable Interest Entity [Line Items]
Current assets	932		4,259	4,259
Long-term assets	5,330		3,690	3,690
Other current liabilities	2,200		3,799	3,799
Net surplus (deficit)	(31,471)		4,151	4,151
Variable Interest Entity, Measure of Activity [Abstract]
Sales	842	$ 2,176	6,933		2,976
Gross loss	(2,425)	(3,191)	(6,168)		(11,411)
Net loss	(2,995)	$ (4,260)	(7,707)		$ (13,952)
Fujitsu Semiconductor Limited \| Aizu Fajitsu Semiconductor Wafer Solution Limited
Variable Interest Entity [Line Items]
Due to controlling owner	22,354
Transphorm, Inc. \| Aizu Fajitsu Semiconductor Wafer Solution Limited
Variable Interest Entity [Line Items]
Due to Transphorm	$ 13,179		0	0
GaNovation \| Aizu Fajitsu Semiconductor Wafer Solution Limited
Variable Interest Entity [Line Items]
Due to controlling owner			$ (1)	$ (1)

Debts - Narrative (Details)					1 Months Ended			3 Months Ended		12 Months Ended
Debts - Narrative (Details)	Oct. 04, 2021 USD ($) $ / shares shares	Jul. 16, 2021 USD ($)	Jun. 29, 2020 USD ($)	Feb. 12, 2020 shares $ / shares	Oct. 31, 2021 USD ($) shares	Jul. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2020 USD ($)	Jan. 10, 2022 $ / shares	Jun. 30, 2021 USD ($)	May 18, 2021 USD ($)	May 17, 2021 USD ($)	Mar. 01, 2021 USD ($)	Dec. 31, 2019 USD ($)	Jul. 31, 2019 USD ($)	Mar. 31, 2019 USD ($)	Apr. 04, 2018 USD ($)	Oct. 31, 2017 USD ($)
Debt Instrument [Line Items]
Principal amount of term loans outstanding								$ 12,180,000		$ 12,180,000
Interest expense									$ (187,000)	(792,000)	$ (760,000)
Changes in fair value of promissory note									699,000	(605,000)	(927,000)
Conversion price per share on convertible note payable (in dollars per share) \| $ / shares	$ 5.00			$ 5.12
Exercise price (in usd per share) \| $ / shares												$ 3.30
Other income									314,000	$ 3,819,000	2,157,000
Term of cooperation and development agreement.							3 years			3 years
Revenue for services rendered								346,000	505,000	$ 346,000
Yaskawa
Debt Instrument [Line Items]
Letter of intent for development activities							$ 4,000,000
Proceeds from collaborators						$ 750,000	1,000,000			1,800,000
Revenue recognized for collaboration development activities									333,000	1,100,000	333,000
Revenue for services rendered								375,000		375,000
Yaskawa
Debt Instrument [Line Items]
Conversion price per share on convertible note payable (in dollars per share) \| $ / shares	$ 5.00			$ 5.12
Number of shares issued (in shares) \| shares	3,120,000
Warrant to purchase shares issued, number of shares	$ 650,000
Exercise price (in usd per share) \| $ / shares	$ 6.00
Exercisable period of warrants (in years)	3 years
Accounts Payable and Accrued Liabilities
Debt Instrument [Line Items]
Interest expense									(153,000)	(685,000)	(915,000)
Loan and Security Agreement (LSA)
Debt Instrument [Line Items]
Long-term loan facility																				$ 15,000,000
Principal amount of term loans outstanding							10,000,000	$ 0	10,000,000	0	10,000,000
Tranche A Loan
Debt Instrument [Line Items]
Long-term loan facility																				5,000,000
Repayment of Nexperia debt			$ 5,000,000
Tranche B Loan
Debt Instrument [Line Items]
Long-term loan facility													$ 8,000,000			$ 8,000,000		$ 8,000,000	$ 8,000,000	10,000,000
Repayment of Nexperia debt		$ 8,000,000
Tranche B-1 Loan
Debt Instrument [Line Items]
Long-term loan facility														$ 2,000,000	$ 2,000,000	2,000,000	$ 2,000,000		$ 2,000,000
Repayment of Nexperia debt		$ 8,000,000
Tranche C Note
Debt Instrument [Line Items]
Long-term loan facility																				12,000,000
Revolving loan																$ 10,000,000				$ 10,000,000
Interest rate per annum																				6.00%
Interest expense accrued									150,000	$ 715,000	610,000
Yaskawa Note
Debt Instrument [Line Items]
Interest rate per annum								1.00%		1.00%											1.00%
Interest expense									(37,000)	$ (77,000)	(150,000)
Changes in fair value of promissory note									(699,000)	605,000	(927,000)
Unsecured subordinated convertible promissory note					$ 15,600,000			$ 0	15,523,000	0											$ 15,000,000
Maximum number of shares of common stock issuable (in shares) \| shares				3,076,171
Accrued interest on promissory note							$ 486,000	0	523,000	0	486,000
Yaskawa Note \| Yaskawa
Debt Instrument [Line Items]
Interest expense accrued									$ 37,000	77,000	$ 150,000
Principal and unpaid interest of convertible note	$ 15,600,000
Number of shares issued (in shares) \| shares					3,120,000
Other income								$ 1,200,000		$ 1,200,000
Accrued interest on promissory note	$ 600,000

Debts - Notes payable (Details) - Yaskawa Note - USD ($) $ in Thousands	Mar. 31, 2022	Oct. 31, 2021	Mar. 31, 2021	Oct. 31, 2017
Line of Credit Facility [Line Items]
Interest rate per annum	1.00%			1.00%
Unsecured subordinated convertible promissory note	$ 0	$ 15,600	$ 15,523	$ 15,000
Promissory note	$ 0		$ 16,128

Debts - Maturities schedule (Details) $ in Thousands	Mar. 31, 2022 USD ($)
Debt Disclosure [Abstract]
2023	$ 180
2024	12,000
Total	$ 12,180

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References + Details

Commitments and Contingencies - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2020	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitment to acquire equipment and services		$ 7,400
Cumulative purchases made to date		7,300
Reimbursement received from government agency		7,200
Amount purchased		369
Remaining accounts payable to vendors		131
Contract for epiwafer technology				$ 900
Option in addition to contract for epiwafer technology				$ 500
Amounts billed and received on government contracts		211
Rent expense	$ 212	918	$ 892
Rental income from noncancelable sublease	$ 30	0	$ 182
Future minimum rental payments to be received under sublease		$ 0

Commitments and Contingencies - Operating lease maturity schedule (Details) $ in Thousands	Mar. 31, 2022 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2023	$ 681
2024	647
2025	156
Total	$ 1,484

Stockholders' Equity (Deficit) - Narrative (Details) $ / shares in Units, $ in Thousands											1 Months Ended			2 Months Ended	3 Months Ended	12 Months Ended
	Jun. 02, 2022 USD ($) $ / shares shares	Jan. 10, 2022 $ / shares shares	Jan. 05, 2022 shares	Dec. 07, 2021 USD ($) $ / shares shares	Nov. 09, 2021 USD ($) $ / shares shares	Oct. 04, 2021 $ / shares shares	Aug. 13, 2021 USD ($) $ / shares shares	Mar. 31, 2021 USD ($) $ / shares shares	Dec. 23, 2020 USD ($) $ / shares shares	Feb. 12, 2020 $ / shares shares	Oct. 31, 2021 USD ($) shares	Apr. 30, 2021 USD ($) shares	Feb. 27, 2020 USD ($) $ / shares shares	Feb. 28, 2022 shares	Mar. 31, 2021 USD ($) $ / shares shares	Mar. 31, 2022 USD ($) vote $ / shares shares	Dec. 31, 2020 USD ($) shares	Feb. 10, 2022 $ / shares shares	Nov. 05, 2021 $ / shares shares	Feb. 11, 2020 shares	Dec. 31, 2019 shares	Oct. 31, 2017 USD ($)
Class of Stock [Line Items]
Common stock, shares issued (in shares)								40,531,996		4,171,571					40,531,996	53,379,307				50,325,662
Common stock, shares outstanding (in shares)								40,531,996		4,171,571					40,531,996	53,379,307				50,325,662
Shares issued in connection with the Reverse Merger (in shares)										1,650,000
Common stock, shares authorized (in shares)								750,000,000							750,000,000	750,000,000
Common stock, par value (in usd per share) \| $ / shares								$ 0.0001							$ 0.0001	$ 0.0001
Number of shares sold in private placement offering (in shares)												97,099
Aggregate gross proceeds from closing of offering \| $												$ 500
Term of advertising contract												1 year
Shares withheld to satisfy employee withholding tax obligations (in shares)														97,249
Preferred stock, shares outstanding (in shares)																0
Preferred stock, shares issued (in shares)																0
Placement agent fees and closing expenses \| $															$ 50	$ 1,127	$ 3,133
Number of votes, common stock (per share) \| vote																1
Exercise price (in usd per share) \| $ / shares		$ 3.30
Issuance of common stock for exercise of warrants (in shares)		82,500	13,028
Private Placement
Class of Stock [Line Items]
Number of shares sold in private placement offering (in shares)				1,673,152	6,600,000		1,000,000	250,000	5,000,000				5,380,000
Aggregate gross proceeds from closing of offering \| $				$ 12,900	$ 33,000		$ 5,000	$ 1,000	$ 15,000				$ 21,500
Price per share (in dollars per share) \| $ / shares				$ 7.71	$ 5.00		$ 5.00	$ 4.00	$ 3.00				$ 4.00		$ 4.00
Placement agent fees and closing expenses \| $				$ 286	$ 840		$ 22	$ 50	$ 1,400				$ 1,800
Number of common stock issuable from warrants (in shares)							209,000		150,000
Exercise price (in usd per share) \| $ / shares							$ 6.00		$ 3.30
Private Placement, Additional Shares Purchased \| Subsequent Event
Class of Stock [Line Items]
Number of shares sold in private placement offering (in shares)	3,199,999
Aggregate gross proceeds from closing of offering \| $	$ 16,000
Price per share (in dollars per share) \| $ / shares	$ 5.00
Placement agent fees and closing expenses \| $	$ 280
Number of common stock issuable from warrants (in shares)	666,668
Yaskawa
Class of Stock [Line Items]
Number of shares issued (in shares)						3,120,000
Exercise price (in usd per share) \| $ / shares						$ 6.00
Yaskawa Note
Class of Stock [Line Items]
Unsecured subordinated convertible promissory note \| $								$ 15,523			$ 15,600				$ 15,523	$ 0						$ 15,000
Yaskawa Note \| Yaskawa
Class of Stock [Line Items]
Number of shares issued (in shares)											3,120,000
Warrant \| Private Placement
Class of Stock [Line Items]
Placement agent fees and closing expenses \| $									$ 223
Number of common stock issuable from warrants (in shares)				348,649	416,667	650,000	209,000		150,000									20,233	958,334
Common Stock
Class of Stock [Line Items]
Common stock, shares outstanding (in shares)								40,531,996							40,531,996	53,379,307	40,278,496				4,220,998
Shares redeemed (in shares)																	52,773
Shares issued in connection with the Reverse Merger (in shares)																	1,650,000
Shares withheld to satisfy employee withholding tax obligations (in shares)																97,249
Price per share (in dollars per share) \| $ / shares										$ 4.00
Issuance of common stock for exercise of warrants (in shares)																95,528
Common Stock \| Private Placement
Class of Stock [Line Items]
Exercise price (in usd per share) \| $ / shares				$ 9.25	$ 6.00	$ 6.00	$ 6.00		$ 3.30									$ 8.48	$ 6.00
Series 1 Preferred Stock
Class of Stock [Line Items]
Convertible preferred stock, shares outstanding (in shares)										51,680,254										51,680,254
Convertible preferred stock, shares issued (in shares)										51,680,254										51,680,254
Common stock, shares issued (in shares)										12,433,953
Common stock, shares outstanding (in shares)										12,433,953
Series 2 Preferred Stock
Class of Stock [Line Items]
Convertible preferred stock, shares outstanding (in shares)										38,760,190										38,760,190
Convertible preferred stock, shares issued (in shares)										38,760,190										38,760,190
Common stock, shares issued (in shares)										7,499,996
Common stock, shares outstanding (in shares)										7,499,996
Series 3 Preferred Stock
Class of Stock [Line Items]
Convertible preferred stock, shares outstanding (in shares)										31,850,304										31,850,304
Convertible preferred stock, shares issued (in shares)										31,850,304										31,850,304
Common stock, shares issued (in shares)										4,000,000
Common stock, shares outstanding (in shares)										4,000,000
Common Stock
Class of Stock [Line Items]
Shares redeemed (in shares)										52,733
Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)																5,000,000

Stockholders' Equity (Deficit) - Reserved common stock (Details)	Mar. 31, 2022 shares
Class of Stock [Line Items]
Common stock reserved for issuance (in shares)	9,365,141
Common stock warrants
Class of Stock [Line Items]
Common stock reserved for issuance (in shares)	2,657,298
Equity incentive plans
Class of Stock [Line Items]
Common stock reserved for issuance (in shares)	6,707,843

Stockholders' Equity (Deficit) - Warrants (Details) - $ / shares	12 Months Ended
	Mar. 31, 2022	Jan. 10, 2022	Feb. 12, 2020	Feb. 11, 2020
Class of Stock [Line Items]
Number of shares (in shares)	2,657,298		15,461	186,535
Exercise price (in usd per share)		$ 3.30
5 years after an initial public offering of the Company
Class of Stock [Line Items]
Number of shares (in shares)	6,046
Exercise price (in usd per share)	$ 34.74
Expiration date	5 years
5 years after an initial public offering of the Company
Class of Stock [Line Items]
Number of shares (in shares)	3,369
Exercise price (in usd per share)	$ 54.41
Expiration date	5 years
December 23, 2025
Class of Stock [Line Items]
Number of shares (in shares)	45,000
Exercise price (in usd per share)	$ 3.30
August 13, 2024
Class of Stock [Line Items]
Number of shares (in shares)	209,000
Exercise price (in usd per share)	$ 6.00
October 4, 2024
Class of Stock [Line Items]
Number of shares (in shares)	650,000
Exercise price (in usd per share)	$ 6.00
November 5, 2024
Class of Stock [Line Items]
Number of shares (in shares)	958,334
Exercise price (in usd per share)	$ 6.00
November 9, 2024
Class of Stock [Line Items]
Number of shares (in shares)	416,667
Exercise price (in usd per share)	$ 6.00
December 7, 2024
Class of Stock [Line Items]
Number of shares (in shares)	348,649
Exercise price (in usd per share)	$ 9.25
December 10, 2025
Class of Stock [Line Items]
Number of shares (in shares)	20,233
Exercise price (in usd per share)	$ 8.48

Stock-Based Compensation - Narrative (Details) - shares	1 Months Ended		3 Months Ended					12 Months Ended
Stock-Based Compensation - Narrative (Details) - shares	Dec. 31, 2020	Sep. 30, 2020	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Mar. 31, 2022	Dec. 31, 2020	Feb. 12, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under company plans (in shares)	2,320,318		2,879,008			2,543,125		2,879,008	2,320,318	2,461,923	2,473,198
Equity Awards outstanding under The 2020 Plan (in shares)						0
Common stock reserved for issuance (in shares)			9,365,141					9,365,141
Percentage of outstanding shares			5.00%					5.00%
Restricted stock granted (in shares)								0
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period								4 years
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting of restricted stock units (in shares)			305,982			3,000	4,000		4,000
Restricted stock granted (in shares)			342,640	307,640	35,000	137,452	816,180		816,180
Percentage vesting				25.00%
Award vesting period				4 years	3 years
Restricted Stock Units (RSUs) \| Period 1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage vesting								33.33%
Restricted Stock Units (RSUs) \| Period 2
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage vesting								33.33%
Restricted Stock Units (RSUs) \| Period 3
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage vesting								33.33%
Restricted Stock Units (RSUs) \| Period 4
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage vesting					25.00%
Award vesting period					1 year
Restricted Stock Awards (RSA)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting of restricted stock units (in shares)		98,450	0			37,051			98,450
Restricted stock granted (in shares)	12,000	123,501	0			0			135,501
The 2020 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under company plans (in shares)			2,879,008					2,879,008
Common stock reserved for issuance (in shares)			2,874,060					2,874,060
Annual increase in shares available for issue (in shares)								2,026,599
Number of shares authorized by 2020 plan (in shares)			5,050,000					5,050,000
The 2020 Equity Incentive Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual increase in shares available for issue (in shares)								5,000,000
Options authorized (in shares)								2,461,923
The 2020 Equity Incentive Plan \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity Awards outstanding under The 2020 Plan (in shares)			954,775					954,775
Transphorm Technology 2007 Stock Plan and 2015 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under company plans (in shares)										29,703,285
Number of shares authorized by 2020 plan (in shares)			2,588,077					2,588,077

Stock-Based Compensation - Schedule of option activity (Details) - USD ($) $ / shares in Units, $ in Thousands				3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Beginning balance, Options outstanding (in shares)				2,320,318	2,543,125		2,473,198
Options granted (in shares)				223,638	528,077		0
Options exercised (in shares)				(500)	(52,799)		(6,821)
Options cancelled (in shares)				(331)	(139,395)		(146,059)
Ending balance, Options outstanding (in shares)	2,543,125	2,320,318	2,473,198	2,543,125	2,879,008	2,543,125	2,320,318
Exercisable at period end (in shares)	2,283,243	2,267,154		2,283,243	2,206,259	2,283,243	2,267,154
Weighted Average Exercise Price per Share
Beginning of period (in dollars per share)				$ 4.67	$ 4.82		$ 4.67
Options granted (in dollars per share)				6.37	6.31		0
Options exercised (in dollars per share)				3.14	4.19		3.78
Options cancelled (in dollars per share)				9.29	9.52		5.88
End of period (in dollars per share)	$ 4.82	$ 4.67	$ 4.67	4.82	4.88	$ 4.82	4.67
Exercisable at end of period (in usd per share)	$ 4.70	$ 4.70		$ 4.70	$ 4.44	$ 4.70	$ 4.70
Weighted Average Remaining Contractual Term (in Years)
Options outstanding, weighted average remaining contractual term (in years)	6 years 18 days	5 years 11 months 1 day	6 years 10 months 2 days		6 years 7 days	6 years 18 days
Options exercisable, weighted average remaining contractual term (in years)	5 years 7 months 24 days	5 years 10 months 9 days			4 years 11 months 26 days
Aggregate Intrinsic Value (in thousands)
Options outstanding, aggregate intrinsic value	$ 0	$ 0	$ 0	$ 0	$ 6,747	$ 0	$ 0
Options exercisable, aggregate intrinsic value	$ 0	$ 0		$ 0	$ 5,984	$ 0	$ 0
Closing stock price (in dollars per share)	$ 3.75	$ 3.01		$ 3.75	$ 7.07	$ 3.75	$ 3.01

Stock-Based Compensation - Fair value assumptions (Details) - $ / shares	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair market value (in dollars per share)		$ 3.75	$ 6.34
Dividend yield		0.00%	0.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate		0.78%	1.08%
Expected volatility		43.10%	42.50%
Grant date fair value (in usd per share)		$ 0.94	$ 1.94
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate		1.73%	1.32%
Expected volatility		44.30%	43.80%
Grant date fair value (in usd per share)		$ 1.65	$ 3.32
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average expected life (in years)	5 years 10 months 13 days	5 years 2 months 23 days

Stock-Based Compensation - Restricted stock (Details) - $ / shares	1 Months Ended		3 Months Ended					12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Mar. 31, 2022	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Restricted stock granted (in shares)								0
Restricted stock canceled (in shares)			(17,280)			(4,380)			(6,855)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Restricted stock cancelled (in dollars per share)			$ 3.98			$ 4.00			$ 4,000.00
Restricted Stock Awards (RSA)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Restricted stock at beginning of period (in shares)						37,051		0	0
Restricted stock granted (in shares)	12,000	123,501	0			0			135,501
Restricted stock vested (in shares)		(98,450)	0			(37,051)			(98,450)
Restricted stock at end of period (in shares)	37,051		0			0		0	37,051
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Restricted stock at beginning of period (in dollars per share)						$ 4.00			$ 0
Restricted stock granted (in dollars per share)			$ 0			0			3.91
Restricted stock vested (in dollars per share)			$ 0			$ 4.00			3.88
Restricted stock at end of period (in dollars per share)	$ 4.00								$ 4.00
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Restricted stock at beginning of period (in shares)						805,325		935,397	0
Restricted stock granted (in shares)			342,640	307,640	35,000	137,452	816,180		816,180
Restricted stock vested (in shares)			(305,982)			(3,000)	(4,000)		(4,000)
Restricted stock at end of period (in shares)	805,325		954,775			935,397		954,775	805,325
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Restricted stock at beginning of period (in dollars per share)						$ 4,000.00		$ 3.96	$ 0
Restricted stock granted (in dollars per share)			$ 6.31			3.75			4,000.00
Restricted stock vested (in dollars per share)			3.98			3.75			4,000.00
Restricted stock at end of period (in dollars per share)	$ 4,000.00		$ 4.61			$ 3.96		$ 4.61	$ 4,000.00

Stock-Based Compensation - Share-based payment arrangement, expense (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2020
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock based compensation expense	$ 2,614	$ 513	$ 1,525
Cost of revenue
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock based compensation expense	161	39	93
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock based compensation expense	552	115	306
Sales and marketing
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock based compensation expense	190	33	68
General and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock based compensation expense	$ 1,711	$ 326	$ 1,058

Stock-Based Compensation - Unrecognized stock-based compensation (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total	$ 3,989	$ 3,018
Average Expected Recognition Period (in years)	1 year 9 months 3 days	2 years 25 days
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options	$ 1,413	$ 280
Average Expected Recognition Period (in years)	2 years 1 month 9 days	5 years 21 days
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock	$ 2,576	$ 2,738
Average Expected Recognition Period (in years)	1 year 6 months 25 days	1 year 9 months 3 days

Fair Value Measurements - Fair value hierarchy (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Mar. 31, 2022	Mar. 31, 2021
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Promissory note	$ 0	$ 0
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Promissory note	0	0
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Promissory note	$ 0	$ 16,128

Fair Value Measurements - Changes in level 3 inputs (Details) - Yaskawa Note - Yaskawa - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2020
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value at beginning of period	$ 15,392	$ 16,128	$ 16,169
Interest expense accrued	37	77	150
Increase (decrease) in fair value	699	(605)	(927)
Conversion		(15,600)
Fair value at period end	$ 16,128	$ 0	$ 15,392

Fair Value Measurements - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2020	Oct. 04, 2021
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Number of common stock shares converted per preferred share (in shares)				3,120,000
Interest expense	$ 187	$ 792	$ 760
Changes in fair value of promissory note	(699)	605	927
Yaskawa Note
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Accrued interest on promissory note	523	0	486
Interest expense	37	77	150
Changes in fair value of promissory note	$ 699	$ (605)	$ 927
Yaskawa Note \| Yaskawa
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Principal and unpaid interest of convertible note				$ 15,600
Principal amount of long term loan facility				15,000
Accrued interest on promissory note				$ 600
Number of common stock shares converted per preferred share (in shares)				3,120,000

Fair Value Measurements - Fair value measurement inputs (Details)	Mar. 31, 2021 $ / shares
Stock price (in usd per share)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Promissory note, fair value measurement inputs	3.75
Time
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Promissory note, expected term	1 year 6 months
Risk-free rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Promissory note, fair value measurement inputs	0.0012
Volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Promissory note, fair value measurement inputs	0.506

401(k) Savings Plan (Details) - USD ($)	3 Months Ended	12 Months Ended
401(k) Savings Plan (Details) - USD ($)	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2020
Retirement Benefits [Abstract]
Employer discretionary contributions to 401K plan	$ 0	$ 0	$ 0

Income Taxes - Narrative (Details) - USD ($)	3 Months Ended	12 Months Ended
Income Taxes - Narrative (Details) - USD ($)	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2020
Operating Loss Carryforwards [Line Items]
Loss before tax expense	$ 6,579,000	$ 10,235,000	$ 17,909,000
Tax expense	0	0	0
Valuation allowance	53,500,000	56,600,000
Increase in unrecognized tax benefits	0	0	0
Decrease in unrecognized tax benefits	0	0	0
Unrecognized tax benefits, penalties	0	0	0
Unrecognized tax benefits, interest	0	0	0
Unrecognized tax benefits, accrued interest and penalties	0	0
Research Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Research tax credit carryforward		4,300,000
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Loss before tax expense	4,900,000	(8,800,000)	10,300,000
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Tax expense	0	0	0
Operating loss carryforwards		258,900,000
Operating loss carryforwards subject to expiration		207,500,000
Domestic Tax Authority \| Research Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Research tax credit carryforward		5,000,000
Domestic Tax Authority \| Tax Year 2022
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards		9,800,000
Domestic Tax Authority \| Tax Year 2021
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	4,500,000
Domestic Tax Authority \| Tax Year 2020
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards			10,500,000
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Tax expense	1,000	1,000	1,000
Operating loss carryforwards subject to expiration		154,000,000
State and Local Jurisdiction \| Tax Year 2022
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards		2,600,000
State and Local Jurisdiction \| Tax Year 2021
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	1,000,000
State and Local Jurisdiction \| Tax Year 2020
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards			2,600,000
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Tax expense	0	0	0
Operating loss carryforwards		6,500,000
Foreign Tax Authority \| National Tax Agency, Japan
Operating Loss Carryforwards [Line Items]
Loss before tax expense	1,700,000	(1,400,000)	7,600,000
Foreign Tax Authority \| National Tax Agency, Japan \| Transphorm Japan, Inc.
Operating Loss Carryforwards [Line Items]
Loss before tax expense		(1,200,000)	800,000
Foreign Tax Authority \| National Tax Agency, Japan \| Transphorm Ailzu, Inc.
Operating Loss Carryforwards [Line Items]
Loss before tax expense	$ 1,500,000	(627,000)	6,800,000
Foreign Tax Authority \| National Tax Agency, Japan \| Transphorm Epi, Inc.
Operating Loss Carryforwards [Line Items]
Loss before tax expense		$ 344,000	$ (25,000)

Income Taxes - Deferred tax assets (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Mar. 31, 2021
Deferred tax assets:
Net operating loss carryforwards	$ 49,715	$ 47,424
Tax credits	6,171	5,444
California capitalized research and development	40	72
Others, net	564	581
Total deferred tax assets	56,490	53,521
Valuation allowance	(56,550)	(53,481)
Deferred tax asset, net of valuation allowance	(60)	40
Deferred tax liabilities:
Fixed assets	60	(40)
Total deferred tax liabilities	60	(40)
Net deferred tax assets	$ 0	$ 0

Income Taxes - Effective income tax rate reconciliation (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Federal statutory income tax rate	21.00%	21.00%	21.00%
Research and development credit	2.73%	7.10%	4.06%
Nondeductible expense	(2.43%)	1.80%	0.64%
Loss in joint venture	(6.76%)	(1.87%)	(11.70%)
Foreign income tax rate difference	2.45%	1.39%	4.10%
Others, net	0.85%	(0.40%)	(2.08%)
Valuation allowance	(17.84%)	(29.02%)	(16.02%)
Effective tax rate	0.00%	0.00%	0.00%

Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2020
Related Party Transaction
Other income		$ 314	$ 3,819	$ 2,157
Accounts receivable due from related party	$ 1,200	14,100	1,200
Corporate Joint Venture
Related Party Transaction
Revenue from related parties			476
Accounts receivable due from related party	719	13,500	719
Noncontrolling Common Stockholder
Related Party Transaction
Accounts payable to related party	760	370	760
Noncontrolling Common Stockholder \| Nexperia
Related Party Transaction
Accounts payable to related party	102	11	102
Noncontrolling Common Stockholder \| Furukawa
Related Party Transaction
Accrued royalties		4
Yaskawa \| Yaskawa Note
Related Party Transaction
Other income	1,200		1,200
GaNovation
Related Party Transaction
Accounts receivable due from related party		5
Common Stockholder
Related Party Transaction
Accounts receivable due from related party	$ 515	503	515
Other Income \| Corporate Joint Venture
Related Party Transaction
Gain on termination of JVA and settlement of obligation			1,500
Related Party Services \| Corporate Joint Venture
Related Party Transaction
Related party transaction expenses		406	3,100	241
Research and development \| Corporate Joint Venture
Related Party Transaction
Related party transaction expenses		144	456	919
Research and development \| Common Stockholder
Related Party Transaction
Reduction in license maintenance fees				408
Purchase of Inventory \| Corporate Joint Venture
Related Party Transaction
Related party transaction expenses			181
Consumption Tax \| Corporate Joint Venture
Related Party Transaction
Related party transaction expenses			140
Commitment For Services \| Corporate Joint Venture
Related Party Transaction
Related party transaction expenses		9	343
Sale of Products \| Noncontrolling Common Stockholder
Related Party Transaction
Revenue from related parties		12	19	165
Sale of Products \| Yaskawa
Related Party Transaction
Revenue from related parties			1,500
Sale of Products \| Common Stockholder
Related Party Transaction
Revenue from related parties		304	1,700	915
License Maintenance Fee \| Noncontrolling Common Stockholder
Related Party Transaction
Related party transaction expenses		54	111	200
License Maintenance Fee \| Common Stockholder
Related Party Transaction
Reduction in license maintenance fees		38	150	150
Consulting Expense \| Noncontrolling Common Stockholder
Related Party Transaction
Related party transaction expenses			176
Service Expense \| Corporate Joint Venture
Related Party Transaction
Related party transaction expenses			12
License Fee Income \| Common Stockholder
Related Party Transaction
Revenue from related parties		357	8,500	5,200
Interest Expense \| Common Stockholder
Related Party Transaction
Related party transaction expenses		$ 150	$ 714	610
Reimbursement for research and development \| Corporate Joint Venture
Related Party Transaction
Related party transaction expenses				408
Other Expense \| Corporate Joint Venture
Related Party Transaction
Related party transaction expenses				84
EPI Gen 4 wafer growth sales \| Common Stockholder
Related Party Transaction
Revenue from related parties				$ 701

Subsequent Events (Details) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended	12 Months Ended
Subsequent Events (Details) - USD ($) $ in Thousands	Jun. 02, 2022	Apr. 30, 2021	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2020
Subsequent Event [Line Items]
Number of shares sold in private placement offering (in shares)		97,099
Aggregate gross proceeds from closing of offering		$ 500
Placement agent fees and closing expenses			$ 50	$ 1,127	$ 3,133
Subsequent Event \| Private Placement, Additional Shares Purchased
Subsequent Event [Line Items]
Number of shares sold in private placement offering (in shares)	3,199,999
Aggregate gross proceeds from closing of offering	$ 16,000
Number of common stock issuable from warrants (in shares)	666,668
Placement agent fees and closing expenses	$ 280