Alpha and Omega Semiconductor Limited (AOSL) 10-Q 8 Feb 21 2021 Q2 Quarterly report Financial data

Cover

Cover - shares	6 Months Ended
	Dec. 31, 2020	Jan. 25, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Dec. 31, 2020
Document Transition Report	false
Entity File Number	001-34717
Entity Registrant Name	Alpha and Omega Semiconductor Limited
Entity Incorporation, State or Country Code	D0
Entity Tax Identification Number	77-0553536
Entity Address, Address Line One	Clarendon House
Entity Address, Address Line Two	2 Church Street
Entity Address, City or Town	Hamilton
Entity Address, Postal Zip Code	HM 11
Entity Address, Country	BM
City Area Code	408
Local Phone Number	830-9742
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Title of 12(b) Security	Common Shares
Trading Symbol	AOSL
Security Exchange Name	NASDAQ
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		25,770,998
Entity Central Index Key	0001387467
Current Fiscal Year End Date	--06-30
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q2
Amendment Flag	false

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 30, 2020
Current assets:
Cash and cash equivalents	$ 180,966	$ 158,536
Restricted cash	230	2,190
Accounts receivable, net	24,934	13,272
Inventories	144,307	135,528
Other current assets	10,833	8,807
Total current assets	361,270	318,333
Property, plant and equipment, net	430,808	412,340
Operating lease right-of-use assets, net	34,395	32,948
Intangible assets, net	15,090	16,770
Deferred income tax assets	4,852	4,766
Restricted cash - long-term	2,143	1,978
Other long-term assets	4,607	5,804
Total assets	853,165	792,939
Current liabilities:
Accounts payable	83,859	86,181
Accrued liabilities	60,483	54,986
Income taxes payable	2,166	1,360
Short-term debt	43,574	30,114
Finance lease liabilities	16,535	15,258
Operating lease liabilities	4,896	4,159
Total current liabilities	211,513	192,058
Long-term debt	93,096	99,775
Income taxes payable - long-term	921	903
Deferred income tax liabilities	860	496
Finance lease liabilities - long-term	20,821	26,842
Operating lease liabilities - long-term	31,102	30,254
Other long-term liabilities	20,196	10,723
Total liabilities	378,509	361,051
Commitments and contingencies (Note 10)
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred shares, par value $0.002 per share: Authorized: 10,000 shares; issued and outstanding: none at December 31, 2020 and June 30, 2020	0	0
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Common shares, par value $0.002 per share: Authorized: 100,000 shares; issued and outstanding: 32,394 shares and 25,765 shares, respectively at December 31, 2020 and 31,944 shares and 25,305 shares, respectively at June 30, 2020	65	64
Treasury shares at cost: 6,629 shares at December 31, 2020 and 6,639 shares at June 30, 2020	(66,097)	(66,184)
Additional paid-in capital	254,980	246,103
Accumulated other comprehensive income (loss)	1,481	(5,127)
Retained earnings	141,289	118,833
Total Alpha and Omega Semiconductor Limited shareholder's equity	331,718	293,689
Noncontrolling interest	142,938	138,199
Total equity	474,656	431,888
Total liabilities and equity	$ 853,165	$ 792,939
Common Stock, Par or Stated Value Per Share	$ 0.002	$ 0.002

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2020	Jun. 30, 2020
Preferred stock, par value (in dollars per share)	$ 0.002	$ 0.002
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common shares, par value (in dollars per share)	$ 0.002	$ 0.002
Common shares, authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	32,394,000	31,944,000
Common stock, shares outstanding (in shares)	25,765,000	25,305,000
Treasury shares (in shares)	6,629,000	6,639,000

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Income Statement [Abstract]
Revenue	$ 158,830	$ 117,860	$ 310,381	$ 235,662
Cost of goods sold	110,081	93,454	219,109	184,324
Gross profit	48,749	24,406	91,272	51,338
Operating expenses
Research and development	15,423	12,147	30,114	24,515
Selling, general and administrative	19,736	15,629	37,241	30,814
Total operating expenses	35,159	27,776	67,355	55,329
Operating income (loss)	13,590	(3,370)	23,917	(3,991)
Interest expense and other income (loss), net	(381)	(635)	(930)	(1,462)
Income (loss) before income taxes	13,209	(4,005)	22,987	(5,453)
Income tax expense	669	568	1,680	978
Net income (loss) including noncontrolling interest	12,540	(4,573)	21,307	(6,431)
Net loss attributable to noncontrolling interest	(363)	(3,568)	(1,170)	(6,435)
Net income (loss) attributable to Alpha and Omega Semiconductor Limited	$ 12,903	$ (1,005)	$ 22,477	$ 4
Net income (loss) per common share attributable to Alpha and Omega Semiconductor Limited
Basic (in dollars per share)	$ 0.50	$ (0.04)	$ 0.88	$ 0
Diluted (in dollars per share)	$ 0.47	$ (0.04)	$ 0.84	$ 0
Weighted average number of common shares attributable to Alpha and Omega Semiconductor Limited used to compute net income (loss) per share
Basic (in shares)	25,672	24,701	25,506	24,620
Diluted (in shares)	27,353	24,701	26,834	25,362

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Net loss including noncontrolling interest	$ 12,540	$ (4,573)	$ 21,307	$ (6,431)
Other comprehensive income (loss), net of tax
Foreign currency translation adjustment	6,814	3,055	12,517	(3,096)
Comprehensive income (loss)	19,354	(1,518)	33,824	(9,527)
Less: Noncontrolling interest	2,824	(2,150)	4,739	(7,985)
Comprehensive income (loss) attributable to Alpha and Omega Semiconductor Limited	$ 16,530	$ 632	$ 29,085	$ (1,542)

CONSOLIDATED STATEMENTS OF SHAR

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Total AOS Shareholders' Equity	Common Shares	Treasury Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Noncontrolling Interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, including portion attributable to noncontrolling interest	$ 443,289
Beginning balance at Jun. 30, 2019		$ 291,024	$ 62	$ (66,240)	$ 234,410	$ (2,693)	$ 125,485
Beginning balance, noncontrolling interest at Jun. 30, 2019								$ 152,265
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of common stock options and release of restricted stock units (in shares)			0
Exercise of common stock options and release of restricted stock units	26	26			26
Beginning balance, including portion attributable to noncontrolling interest	440,150
Reissuance of treasury stock upon exercise of common stock options and release of restricted stock units	0	0		13			(13)
Withholding tax on restricted stock units	(195)	(195)			(195)
Issuance of shares under ESPP (in shares)			1
Issuance of shares under ESPP	1,701	1,701			1,700
Share-based compensation	4,856	4,856			4,856
Net loss	4	4					4
Net loss attributable to noncontrolling interest	(6,435)							(6,435)
Net loss including noncontrolling interest	(6,431)
Cumulative translation adjustment		(1,546)				(1,546)
Cumulative translation adjustment, attributable to noncontrolling interest								(1,550)
Cumulative translation adjustment, including portion attributable to noncontrolling interest	(3,096)
Ending balance at Dec. 31, 2019		295,870	$ 63	(66,227)	240,797	(4,239)	125,476
Ending balance, noncontrolling interest at Dec. 31, 2019								144,280
Ending balance, including portion attributable to noncontrolling interest at Dec. 31, 2019	440,150
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, including portion attributable to noncontrolling interest	437,553
Beginning balance at Sep. 30, 2019		291,123	$ 62	(66,227)	236,683	(5,876)	126,481
Beginning balance, noncontrolling interest at Sep. 30, 2019								146,430
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of common stock options and release of restricted stock units (in shares)			0
Exercise of common stock options and release of restricted stock units	26	26			26
Beginning balance, including portion attributable to noncontrolling interest	440,150
Withholding tax on restricted stock units	(99)	(99)			(99)
Issuance of shares under ESPP (in shares)			1
Issuance of shares under ESPP	1,701	1,701			1,700
Share-based compensation	2,487	2,487			2,487
Net loss	(1,005)	(1,005)					(1,005)
Net loss attributable to noncontrolling interest	(3,568)							(3,568)
Net loss including noncontrolling interest	(4,573)
Cumulative translation adjustment		1,637				1,637
Cumulative translation adjustment, attributable to noncontrolling interest								1,418
Cumulative translation adjustment, including portion attributable to noncontrolling interest	3,055
Ending balance at Dec. 31, 2019		295,870	$ 63	(66,227)	240,797	(4,239)	125,476
Ending balance, noncontrolling interest at Dec. 31, 2019								144,280
Ending balance, including portion attributable to noncontrolling interest at Dec. 31, 2019	440,150
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, including portion attributable to noncontrolling interest	440,150
Beginning balance, including portion attributable to noncontrolling interest	431,888
Beginning balance at Jun. 30, 2020	293,689	293,689	$ 64	(66,184)	246,103	(5,127)	118,833
Beginning balance, noncontrolling interest at Jun. 30, 2020	138,199							138,199
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of common stock options and release of restricted stock units (in shares)			0
Exercise of common stock options and release of restricted stock units	1,495	1,495			1,495
Beginning balance, including portion attributable to noncontrolling interest	474,656
Reissuance of treasury stock upon exercise of common stock options and release of restricted stock units	66	66		87			(21)
Withholding tax on restricted stock units	(953)	(953)			(953)
Issuance of shares under ESPP (in shares)			1
Issuance of shares under ESPP	1,636	1,636			1,635
Share-based compensation	4,700	4,700			4,700
Restricted stock units settlement in connection with service	2,000	2,000			2,000
Net loss	22,477	22,477					22,477
Net loss attributable to noncontrolling interest	(1,170)							(1,170)
Net loss including noncontrolling interest	21,307
Cumulative translation adjustment		6,608				6,608
Cumulative translation adjustment, attributable to noncontrolling interest								5,909
Cumulative translation adjustment, including portion attributable to noncontrolling interest	12,517
Ending balance at Dec. 31, 2020	331,718	331,718	$ 65	(66,097)	254,980	1,481	141,289
Ending balance, noncontrolling interest at Dec. 31, 2020	142,938							142,938
Ending balance, including portion attributable to noncontrolling interest at Dec. 31, 2020	474,656
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, including portion attributable to noncontrolling interest	449,222
Beginning balance at Sep. 30, 2020		309,108	$ 64	(66,171)	248,967	(2,146)	128,394
Beginning balance, noncontrolling interest at Sep. 30, 2020								140,114
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of common stock options and release of restricted stock units (in shares)			0
Exercise of common stock options and release of restricted stock units	1,495	1,495			1,495
Beginning balance, including portion attributable to noncontrolling interest	474,656
Reissuance of treasury stock upon exercise of common stock options and release of restricted stock units	66	66		74			(8)
Withholding tax on restricted stock units	(541)	(541)			(541)
Issuance of shares under ESPP (in shares)			1
Issuance of shares under ESPP	1,636	1,636			1,635
Share-based compensation	2,424	2,424			2,424
Restricted stock units settlement in connection with service	1,000	1,000			1,000
Net loss	12,903	12,903					12,903
Net loss attributable to noncontrolling interest	(363)							(363)
Net loss including noncontrolling interest	12,540
Cumulative translation adjustment		3,627				3,627
Cumulative translation adjustment, attributable to noncontrolling interest								3,187
Cumulative translation adjustment, including portion attributable to noncontrolling interest	6,814
Ending balance at Dec. 31, 2020	331,718	$ 331,718	$ 65	$ (66,097)	$ 254,980	$ 1,481	$ 141,289
Ending balance, noncontrolling interest at Dec. 31, 2020	142,938							$ 142,938
Ending balance, including portion attributable to noncontrolling interest at Dec. 31, 2020	474,656
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance, including portion attributable to noncontrolling interest	$ 474,656

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities
Net loss including noncontrolling interest	$ 21,307	$ (6,431)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	25,689	21,754
Share-based compensation expense	6,100	4,856
Deferred income taxes, net	278	(148)
Loss on disposal of property and equipment	40	89
Changes in assets and liabilities:
Accounts receivable, net	(11,662)	(9,576)
Inventories	(8,779)	(4,856)
Other current and long-term assets	(1,793)	940
Accounts payable	(370)	(5,676)
Income taxes payable	824	453
Accrued and other liabilities	14,299	6,306
Net cash provided by operating activities	45,933	7,711
Cash flows from investing activities
Purchases of property and equipment excluding JV Company	(14,842)	(20,354)
Purchases of property and equipment in JV Company	(9,926)	(12,067)
Proceeds from sale of property and equipment	10	0
Government grant related to equipment	119	1,254
Net cash used in investing activities	(24,639)	(31,167)
Cash flows from financing activities
Withholding tax on restricted stock units	(953)	(195)
Proceeds from exercise of stock options and ESPP	3,197	1,727
Proceeds from borrowings	31,008	33,708
Repayments of borrowings	(29,912)	(20,863)
Principal payments on finance leases	(8,119)	(3,403)
Net cash provided by (used in) financing activities	(4,779)	10,974
Effect of exchange rate changes on cash, cash equivalents and restricted cash	4,120	(347)
Net increase (decrease) in cash, cash equivalents and restricted cash	20,635	(12,829)
Cash, cash equivalents and restricted cash at beginning of period	162,704	124,295
Cash, cash equivalents and restricted cash at end of period	183,339	111,466
Supplemental disclosures of non-cash investing and financing information:
Property and equipment purchased but not yet paid	$ 12,621	$ 18,165

The Company and Significant Acc

The Company and Significant Accounting Policies	6 Months Ended
	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
The Company and Significant Accounting Policies	The Company and Significant Accounting Policies The Company Alpha and Omega Semiconductor Limited and its subsidiaries (the “Company”, "AOS", "we" or "us") design, develop and supply a broad range of power semiconductors. The Company's portfolio of products targets high-volume applications, including personal and portable computers, graphic cards, flat panel TVs, home appliances, smart phones, battery packs, quick chargers, home appliances, consumer and industrial motor controls and power supplies for TVs, computers, servers and telecommunications equipment. The Company conducts its operations primarily in the United States of America (“USA”), Hong Kong, China, and South Korea. Basis of Preparation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) for interim financial information and with the instructions to Article 10 of Securities and Exchange Commission Regulation S-X, as amended. They do not include all information and footnotes necessary for a fair presentation of financial position, results of operations and cash flows in conformity with U.S. GAAP for complete financial statements. These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and related notes contained in the Company’s Annual Report on Form 10-K for the fiscal year ended June 30, 2020. All significant intercompany balances and transactions have been eliminated in consolidation. In the opinion of management, all adjustments (consisting of normal recurring adjustments and accruals) considered necessary for a fair presentation of the results of operations for the periods presented have been included in the interim periods. Operating results for the three and six months ended December 31, 2020 are not necessarily indicative of the results that may be expected for the fiscal year ending June 30, 2021 or any other interim period. The condensed consolidated balance sheets at June 30, 2020 is derived from the audited financial statements included in the Company’s Annual Report on Form 10-K for the fiscal year ended June 30, 2020. Reclassification The Company has reclassified certain amounts previously reported in its financial statements to conform to the current presentation. These reclassifications did not have a material impact on our consolidated financial statements. Joint Venture On March 29, 2016, the Company entered into a joint venture contract (the “JV Agreement”) with two investment funds owned by the Municipality of Chongqing (the “Chongqing Funds”), pursuant to which the Company and the Chongqing Funds formed a joint venture, (the “JV Company”), for the purpose of constructing and operating a power semiconductor packaging, testing and 12-inch wafer fabrication facility ("Fab") in the LiangJiang New Area of Chongqing, China (the “JV Transaction”). The Fab is being built in phases. As of December 31, 2020, the Company owns 51%, and the Chongqing Funds own 49% of the equity interest in the JV Company. The Joint Venture is accounted under the provisions of the consolidation guidance since the Company has controlling financial interest. If both parties agree that the termination of the JV Company is the best interest of each party or the JV Company is bankrupt or insolvent where either party may terminate early, after paying the debts of the JV Company, the remaining assets of the JV Company shall be paid to the Chongqing Funds to cover the principal of its total paid-in contributions plus interest at 10% simple annual rate prior to distributing the balance of the JV Company's assets to the Company. The JV Company has reached its targeted production of assembly and testing and is currently ramping up its Phase I of the 12-inch wafer fabrication. Certain Significant Risks and Uncertainties Related to Outbreak of Coronavirus Disease 2019 (“COVID-19”) The COVID-19 pandemic has had and continues to have a negative impact on business and economic activities across the globe. As a result of the COVID-19 pandemic and the global economic downturn and changing consumer behaviors due to various restrictions imposed by governments, the Company has experienced shifting market trends, including an increasing demand in the markets for notebooks, PCs and gaming devices and decreasing demand for mobile phone and industrial products, as more consumers are staying at and working from home. While the Company has recently benefited from the increasing demand of PC related products, there is no guarantee that this trend will continue, and such increasing demand may discontinue or decline as government authorities relax COVID-19 related restrictions. Furthermore, as the COVID-19 pandemic continues and global economic downturn and high unemployment persists, consumer spending may slow down substantially, in which case the Company may experience a significant decline of customer orders for its products, including those designed for PC-related applications, and such decline will adversely affect its financial conditions and results of operations. The extent to which the COVID-19 pandemic may impact the Company's business will depend on future developments which are uncertain, such as the duration of the outbreak, travel restrictions, governmental mandates issued to mitigate the spread of the disease, business closures, economic disruptions, and the effectiveness of actions taken to contain and treat the virus. Accordingly, the COVID-19 pandemic may have a negative impact on the Company's sales and results of operations, the size and duration of which is difficult to predict. Use of Estimates The preparation of the condensed consolidated financial statements in conformity with U.S. GAAP requires the Company to make estimates, judgments and assumptions that affect the reported amounts of assets, liabilities, revenue and expenses. To the extent there are material differences between these estimates and actual results, the Company's condensed consolidated financial statements will be affected. On an ongoing basis, the Company evaluates the estimates, judgments and assumptions including those related to stock rotation returns, price adjustments, allowance for doubtful accounts, inventory reserves, warranty accrual, income taxes, leases, share-based compensation, recoverability of and useful lives for property, plant and equipment and intangible assets, as well as the economic implications of the COVID-19 pandemic. Leases The Company determines if an arrangement is a lease at inception. Operating leases are included in operating lease right-of-use ("ROU") assets, current operating lease liabilities and long-term operating lease liabilities on the Company's condensed consolidated balance sheets. Finance leases are included in property, plant and equipment, current finance lease liabilities and long-term finance leases liabilities on the condensed consolidated balance sheets. Operating lease ROU assets and operating lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term at commencement date. The Company uses an estimate of its incremental borrowing rate based on the information available at the lease commencement date. The operating lease ROU assets also include any lease payments made and exclude lease incentives. Lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise such options. Operating lease expense is generally recognized on a straight-line basis over the lease term. Variable lease payments are expensed as incurred and are not included within the operating lease ROU asset and lease liability calculation. The Company does not record leases on the condensed consolidated balance sheet with a term of one year or less. Revenue recognition The Company determines revenue recognition through the following steps: (1) identification of the contract with a customer; (2) identification of the performance obligations in the contract; (3) determination of the transaction price; (4) allocation of the transaction price to the performance obligations in the contract; and (5) recognition of revenue when, or as, a performance obligation is satisfied. The Company recognizes revenue when product is shipped to the customer, net of estimated stock rotation returns and price adjustments to certain distributors. Packaging and testing services revenue is recognized upon shipment of serviced products to the customer. Share-based Compensation Expense The Company maintains an equity-settled, share-based compensation plan to grant restricted share units and stock options. The Company recognizes expense related to share-based compensation awards that are ultimately expected to vest based on estimated fair values on the date of grant. The fair value of restricted share units is based on the fair value of the Company's common share on the date of grant. For restricted stock awards subject to market conditions, the fair value of each restricted stock award is estimated at the date of grant using the Monte-Carlo pricing model. The fair value of stock options is estimated on the date of grant using the Black-Scholes option valuation model. Share-based compensation expense is recognized on the accelerated attribution basis over the requisite service period of the award, which generally equals the vesting period. Restricted Cash As a condition of the loan agreement, the Company is required to keep a compensating balance at the issuing bank (see Note 5). In addition, the Company maintains restricted cash in connection with cash balances temporarily restricted for regular business operations including the possibility of a dispute with a vendor. These balances have been excluded from the Company’s cash and cash equivalents balance and are classified as restricted cash in the Company’s condensed consolidated balance sheets. As of December 31, 2020 and June 30, 2020, the amount of restricted cash was $2.4 million and $4.2 million, respectively. Fair Value of Financial Instruments The fair value of cash equivalents is categorized in Level 1 in the fair value hierarchy. Cash equivalents consist primarily of short-term bank deposits. The carrying values of financial instruments such as cash and cash equivalents, accounts receivable and accounts payable approximate their carrying values due to their short-term maturities. The carrying value of the company's debt is considered a reasonable estimate of fair value which is estimated by considering the current rates available to the Company for debt of the same remaining maturities, structure, credit risk and terms of the debts. Government Grants The Company occasionally receives government grants that provide financial assistance for certain eligible expenditures in China. These grants include reimbursements on interest expense on bank borrowings, payroll tax credits, credit for property, plant and equipment in a particular geographical location, employment credits, as well as business expansion credits. Government grants are not recognized until there is reasonable assurance that the Company will comply with the conditions attaching to it, and that the grant will be received. The Company records such grants either as a reduction of the related expense, a reduction of the cost of the related asset, or as other income depending upon the nature of the grant. As a result of such grants, during the three and six months ended December 31, 2020, the Company reduced interest expense by $0.7 million and $1.5 million , property, plant and equipment by $0.1 million and $0.1 million, and operating expenses by $1.7 million and $3.6 million, r espectively. During the three and six months ended December 31, 2019, the Company reduced interest expense by $1.1 million and $3.4 million, property, plant and equipment by $1.3 million and $1.3 million, and operating expenses by $0.5 million and $0.5 million, respectively. Long-lived Assets The Company evaluates its long-lived assets for impairment whenever events or changes indicate that the carrying amount of such assets may not be recoverable. Due to the COVID-19 pandemic, the Company assessed the changes in circumstances that occurred since the March 2020 quarter. These factors included operating losses, a decrease in the Company's share price in February and March of 2020, which reduced its market capitalization, expectation of lower business growth for the coming quarters, increased and prolonged economic and regulatory uncertainty in the global economies, and the expectation of higher supply chain costs and increased competition. Therefore, the Company performed a recoverability test by comparing the sum of the estimated undiscounted future cash flows of its long-lived assets to their carrying amount as of June 30, 2020. Some of the more significant assumptions used in the estimated future cash flows include net sales, cost of goods sold, operating expenses, working capital, capital expenditures, income tax rates, and long-term growth rates that appropriately reflects the risks inherent in the future cash flow stream. The Company selected the assumptions used in the financial forecasts by referencing to historical data, supplemented by current and anticipated market conditions, estimated product growth rates and management's plans. These estimated future cash flows were consistent with those the Company uses in its internal planning. The result of the recoverability test indicated that the sum of the expected future cash flows (undiscounted and without interest charges) was greater than the carrying amount of the long-lived assets. Therefore, the Company concluded that the carrying amount of the long-lived assets is recoverable as of June 30, 2020. Comprehensive Income (Loss) Comprehensive income (loss) is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. The Company's accumulated other comprehensive income (loss) consists of cumulative foreign currency translation adjustments. Total comprehensive income (loss) is presented in the condensed consolidated statements of comprehensive income (loss). Recent Accounting Pronouncements Recently Issued Accounting Standards not yet adopted In August 2020, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 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, which, among other things, provides guidance on how to account for contracts on an entity’s own equity. This ASU simplifies the accounting for certain financial instruments with characteristics of liabilities and equity. Specifically, the ASU eliminated the need for the Company to assess whether a contract on the entity’s own equity (1) permits settlement in unregistered shares, (2) whether counterparty rights rank higher than shareholder’s rights, and (3) whether collateral is required. In addition, the ASU requires incremental disclosure related to contracts on the entity’s own equity and clarifies the treatment of certain financial instruments accounted for under this ASU on earnings per share. For public business entities, the ASU is effective for fiscal years beginning after December 15, 2021, and interim periods within those fiscal years. The Company does not expect the adoption of this guidance will have a material impact on its consolidated financial position, results of operations or cash flows. In January 2020, the FASB issued ASU No. 2020-01, “Investments - Equity Securities (Topic 321), Investments - Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815) - Clarifying the Interactions between Topic 321, Topic 323, and Topic 815.” The ASU is based on a consensus of the Emerging Issues Task Force and is expected to increase comparability in accounting for these transactions. ASU 2016-01 made targeted improvements to accounting for financial instruments, including providing an entity the ability to measure certain equity securities without a readily determinable fair value at cost, less any impairment, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. Among other topics, the amendments clarify that an entity should consider observable transactions that require it to either apply or discontinue the equity method of accounting. For public business entities, the amendments in the ASU are effective for fiscal years beginning after December 15, 2020, and interim periods within those fiscal years. The Company does not expect the adoption of this guidance will have a material impact on its consolidated financial position, results of operations or cash flows. In December 2019, the FASB issued ASU No. 2019-12 “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes ("ASU 2019-12") by removing certain exceptions to the general principles. The amendments will be effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. Early adoption of the amendments is permitted. Depending on the amendment, adoption may be applied on a retrospective, modified retrospective or prospective basis. The Company is currently evaluating the impacts of adoption of the new guidance to its consolidated financial statements. Recently Adopted Accounting Standards In August 2018, the FASB issued ASU 2018-15 “Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract". These amendments align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contact with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by these amendments. ASU 2018-15 had no material impact on the Company's consolidated financial statements. In August 2018, the FASB issued ASU 2018-13, “Fair Value Measurement (Topic 820): Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement ("ASU 2018-13”). ASU 2018-13 amends existing fair value measurement disclosure requirements by adding, changing, or removing certain disclosures. The amendments on changes in unrealized gains and losses, the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements, and the narrative description of measurement uncertainty should be applied prospectively for only the most recent interim or annual period presented in the initial fiscal year of adoption. All other amendments should be applied retrospectively to all periods presented upon their effective date. ASU 2018-13 had no material impact on the Company's consolidated financial statements. In June 2016, the FASB issued ASU 2016-13, "Financial Instruments - Credit Losses (Topic 326). Topic 326 adds to U.S. GAAP the current expected credit loss ("CECL") model, a measurement model based on expected losses rather than incurred losses. Under this new standard, an entity recognizes its estimate of expected credit losses as an allowance. The new standard is also intended to reduce the complexity of U.S. GAAP by decreasing the number of credit loss models that entities use to account for debt instruments. The new guidance significantly changes the accounting for credit losses. The Company adopted ASU 2016-13 using the modified-retrospective approach in the first quarter of fiscal 2021 with no impact to its condensed consolidated financial statements. The adoption of Topic 326 did not significantly change the Company's approach to the valuation of trade receivables. The Company determines whether there is an expected loss on its accounts receivable by reviewing all available data, including its customers' latest available financial statements, their credit standing and historical collection experience, as well as current and future market and economic conditions. As of December 31, 2020, the allowance for credit losses on the Company's trade receivables remained immaterial.

Net Income Per Common Share Att

Net Income Per Common Share Attributable to Alpha and Omega Semiconductor Limited	6 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Net Income (Loss) Per Share	Net Income (Loss) Per Common Share Attributable to Alpha and Omega Semiconductor Limited The following table presents the calculation of basic and diluted net income (loss) per share attributable to common shareholders: Three Months Ended December 31, Six Months Ended December 31, 2020 2019 2020 2019 (in thousands, except per share data) Numerator: Net income (loss) attributable to Alpha and Omega Semiconductor Limited $ 12,903 $ (1,005) $ 22,477 $ 4 Denominator: Basic: Weighted average number of common shares used to compute basic net income per share 25,672 24,701 25,506 24,620 Diluted: Weighted average number of common shares used to compute basic net income per share 25,672 24,701 25,506 24,620 Effect of potentially dilutive securities: Stock options, RSUs and ESPP shares 1,681 — 1,328 742 Weighted average number of common shares used to compute diluted net income per share 27,353 24,701 26,834 25,362 Net income (loss) per share attributable to Alpha and Omega Semiconductor Limited: Basic $ 0.50 $ (0.04) $ 0.88 $ 0.00 Diluted $ 0.47 $ (0.04) $ 0.84 $ 0.00 The following potential dilutive securities were excluded from the computation of diluted net income (loss) per share as their effect would have been anti-dilutive: Three Months Ended December 31, Six Months Ended December 31, 2020 2019 2020 2019 (in thousands) (in thousands) Employee stock options and RSUs 7 2,040 66 337 ESPP 35 868 134 597 Total potential dilutive securities 42 2,908 200 934

Concentration of Credit Risk an

Concentration of Credit Risk and Significant Customers	6 Months Ended
	Dec. 31, 2020
Risks and Uncertainties [Abstract]
Concentration of Credit Risk and Significant Customers	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 and review of credit approvals, credit ratings and other monitoring procedures. In some instances, the Company also obtains letters of credit from certain customers. Credit sales, which are mainly on credit terms of 30 to 60 days, are only made to customers who meet the Company's credit requirements, while sales to new customers or customers with low credit ratings are usually made on an advance payment basis. The Company considers its trade accounts receivable to be of good credit quality because its key distributors and direct customers have long-standing business relationships with the Company and the Company has not experienced any significant bad debt write-offs of accounts receivable in the past. The Company closely monitors the aging of accounts receivable from its distributors and direct customers, and regularly reviews their financial positions, where available. In the past, the Company shipped its product indirectly to Huawei and its affiliates (collectively, “Huawei”) through distributors. Typically, the Company sold its products to distributors who then sold to original design manufacturers (“ODMs”) that incorporated our products into end applications that were then shipped to Huawei. While distributor point of sale reports summarize distributor sales to ODMs, the Company must make certain assumptions and estimates in order to determine the amount of revenues attributed to indirect shipment to Huawei. During the fiscal year ended June 30, 2019, the estimated revenues attributed to indirect shipments to Huawei were approximately 2% of total revenues. During the period from May 2019 to December 2019, estimated revenues earned by the Company from shipments indirectly made to Huawei were in the range of $11 million to $13 million. The Company has not shipped any products to Huawei after December 31, 2019. See Note 10. Summarized below are individual customers whose revenue or accounts receivable balances were 10% or higher than the respective total consolidated amounts: Three Months Ended December 31, Six Months Ended December 31, Percentage of revenue 2020 2019 2020 2019 Customer A 28.4 % 31.3 % 28.6 % 30.0 % Customer B 36.4 % 37.0 % 34.8 % 36.0 % December 31, June 30, Percentage of accounts receivable Customer A 17.4 % * Customer B 14.4 % * Customer C 23.6 % 29.8 % Customer D 10.0 % * Customer E * 20.1 % Customer F * 10.4 % Customer G * 10.3 % Customer H * 10.9 % * Less than 10%

Balance Sheet Components

Balance Sheet Components	6 Months Ended
	Dec. 31, 2020
Balance Sheet Related Disclosures [Abstract]
Balance Sheet Components	Balance Sheet Components Accounts receivable, net: December 31, June 30, (in thousands) Accounts receivable $ 47,995 $ 43,394 Less: Allowance for price adjustments (23,031) (30,092) Less: Allowance for doubtful accounts (30) (30) Accounts receivable, net $ 24,934 $ 13,272 Inventories: December 31, June 30, (in thousands) Raw materials $ 58,903 $ 55,377 Work in-process 65,680 61,863 Finished goods 19,724 18,288 $ 144,307 $ 135,528 Other current assets: December 31, June 30, (in thousands) VAT receivable $ 2,194 $ 1,639 Other prepaid expenses 2,976 1,900 Prepaid insurance 1,956 1,520 Prepaid maintenance 746 587 Prepayment to supplier 990 938 Prepaid income tax 1,790 1,991 Customs deposit — 163 Other receivables 181 69 $ 10,833 $ 8,807 Property, plant and equipment, net: December 31, June 30, (in thousands) Land $ 4,877 $ 4,877 Building 63,696 58,875 Manufacturing machinery and equipment 493,487 447,079 Equipment and tooling 26,661 25,398 Computer equipment and software 40,004 38,779 Office furniture and equipment 3,744 3,529 Leasehold improvements 73,716 68,224 Land use rights 9,213 8,502 715,398 655,263 Less: accumulated depreciation (324,344) (291,515) 391,054 363,748 Equipment and construction in progress 39,754 48,592 Property, plant and equipment, net $ 430,808 $ 412,340 Intangible assets, net: December 31, June 30, (in thousands) Patents and technology rights $ 18,037 $ 18,037 Trade name 268 268 Customer relationships 1,150 1,150 19,455 19,455 Less: accumulated amortization (4,634) (2,954) 14,821 16,501 Goodwill 269 269 Intangible assets, net $ 15,090 $ 16,770 Estimated future minimum amortization expense of intangible assets is as follows (in thousands): Year ending June 30, 2021 (Remaining) $ 1,680 2022 3,360 2023 3,286 2024 3,249 2025 3,246 $ 14,821 Other long-term assets: December 31, June 30, (in thousands) Prepayments for property and equipment $ 1,140 $ 2,242 Investment in a privately held company 100 100 Customs deposit 1,184 1,662 Other long-term deposits 916 850 Office leases deposits 1,103 766 Other 164 184 $ 4,607 $ 5,804 Accrued liabilities: December 31, June 30, (in thousands) Accrued compensation and benefits $ 29,115 $ 19,968 Warranty accrual 767 709 Stock rotation accrual 3,893 3,358 Accrued professional fees 2,678 5,868 Accrued inventory 1,157 775 Accrued facilities related expenses 1,682 1,831 Accrued property, plant and equipment 9,924 11,039 Other accrued expenses 5,757 8,017 Customer deposit 4,663 2,813 ESPP payable 847 608 $ 60,483 $ 54,986 The activities in the warranty accrual, included in accrued liabilities, are as follows: Six Months Ended December 31, 2020 2019 (in thousands) Beginning balance $ 709 $ 623 Additions 239 130 Utilization (181) (102) Ending balance $ 767 $ 651 The activities in the stock rotation accrual, included in accrued liabilities, are as follows: Six Months Ended December 31, 2020 2019 (in thousands) Beginning balance $ 3,358 $ 1,921 Additions 4,180 5,990 Utilization (3,645) (4,075) Ending balance $ 3,893 $ 3,836 Other long-term liabilities: December 31, June 30, (in thousands) Customer deposits $ 15,000 * $ 8,000 * Computer software liabilities 960 1,897 Equipment liabilities 1,804 — Deferred payroll taxes 2,432 826 Other long-term liabilities $ 20,196 $ 10,723

Bank Borrowing Bank Borrowing

Bank Borrowing Bank Borrowing	6 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Bank Borrowing	Bank Borrowings Short-term borrowings On November 13, 2020, the JV Company entered into a one-year loan agreement with China Merchant Bank in China. The JV Company can borrow up to Chinese Renminbi ("RMB") 50.0 million, or $7.6 million, based on the currency exchange rate between RMB and U.S. Dollar on November 13, 2020. The loan's interest rates are based on the China one-year loan prime rate ("LPR") plus 1.4% per annum. Interest payments are due quarterly with the entire principal due not later than November 19, 2021. During the three months ended December 31, 2020, the JV Company borrowed RMB 50.0 million, or $7.7 million, at an interest rate of 5.25% per annum. As of December 31, 2020, the outstanding balance of this loan was $7.7 million. On April 15, 2020, the JV Company entered into a one-year loan agreement with China Everbright Bank in China to borrow a maximum of RMB 100.0 million (approximately $14.3 million based on the currency exchange rate between RMB and U.S. Dollar on April 15, 2020), in the amount in RMB or USD. Interest payments are due on the 20th of each month, and the entire principal is due on April 16, 2021. The loan consists of RMB 20 million for working capital borrowing in Chinese yuan and RMB 80 million for borrowing in US dollars that is collateralized by eligible accounts receivable. During the three months ended December 31, 2020, the JV Company borrowed $12.1 million at a fixed interest rate of 2.7% per annum. As of December 31, 2020, the total outstanding balance under the loan was $15.2 million which included RMB 20 million or $3.1 million borrowed during the three months ended June 30, 2020. In October 2019, the Company's subsidiary in China entered into a line of credit facility with Bank of Communications Limited in China. This line of credit matures on February 14, 2021 and is based on the China Base Rate multiplied by 1.05, or 4.99% on October 31, 2019. The purpose of the credit facility is to provide short-term borrowings. The Company could borrow up to approximately RMB 60.0 million or $8.5 million based on the currency exchange rate between the RMB and the U.S. Dollar on October 31, 2019. In October 2020, this line of credit was renewed with the same terms and a maturity date of April 21, 2022. As of December 31, 2020, there was no outstanding balance under the loan. On November 29 and December 4, 2018, the JV Company entered into two, one-year loan agreements with China Merchant Bank and Chongqing LiangJiang New District China Merchants Group Limited Company in China to provide loans for RMB 80 million and RMB 20 million, respectively, or $14.5 million in total based on the currency exchange rate between RMB and U.S. Dollar on December 31, 2018, at varying interest rates. On January 20, 2020, the JV Company renewed the loan agreements with the same terms. Interest payments are due monthly and quarterly with the entire principal due not later than January 21, 2021. As of December 31, 2020, there was no o utstanding balance under the loan. On November 16, 2018, the Company's subsidiary in China entered into a line of credit facility with Industrial and Commercial Bank of China, which expired on September 30, 2019. The purpose of the credit facility was to provide short-term borrowings. The Company could borrow up to approximately RMB 72.0 million or $10.3 million based on currency exchange rate between RMB and U.S. Dollar on November 16, 2018. In December 2020, this line of credit was renewed with the same terms and a maturity date of December 31, 2021. As of December 31, 2020, there was no outstanding balance under the loan. Accounts Receivable Factoring Agreement On August 9, 2019, one of the Company's wholly-owned subsidiaries (the "Borrower") entered into a factoring agreement with the Hongkong and Shanghai Banking Corporation Limited ("HSBC"), whereby the Borrower assigns certain of its accounts receivable with recourse. This factoring agreement allows the Borrower to borrow up to 70% of the net amount of its eligible accounts receivable of the Borrower with a maximum amount of $30.0 million. The interest rate is based on one month London Interbank Offered Rate ("LIBOR") plus 1.75% per annum. The Company is the guarantor for this agreement. The Company is accounting for this transaction as a secured borrowing under the Transfers and Servicing of Financial Assets guidance. In addition, any cash held in the restricted bank account controlled by HSBC has a legal right of offset against the borrowing. This agreement, with certain financial covenants required, has no expiration date. The Borrower was in compliance with these covenants as of December 31, 2020. During the three and six months ended December 31, 2020, the Company borro wed $7.0 million and $36.7 million, respectively, and repaid each amount in full. As of December 31, 2020, there was no outstanding balance and the Company had unused credit of approximately $30.0 million . Credit Facilities On May 9, 2018 (the “Effective Date”), the JV Company entered into a lease finance agreement and a security agreement (the “Agreements”) with YinHai Leasing Company and China Import/Export Bank (the “Lenders”). Pursuant to the Agreements, the Lenders agreed to provide an aggregate of RMB 400.0 million, or $62.8 million based on the currency exchange rate between RMB and U.S. Dollar on the Effective Date, of financing to the JV Company (the “Lease Financing”). In exchange for the Lease Financing, the JV Company agreed to transfer title of its assembly and testing equipment to the Lenders, and the Lenders leased such equipment to the JV Company under a five-year lease arrangement, pursuant to which the JV Company makes quarterly lease payments to the Lenders consisting of principal and interest based on a repayment schedule mutually agreed by the parties. The interest under the Lease Financing is accrued based on the China Base Rate multiplied by 1.15, or 5.4625% on the Effective Date. Under the Agreements, at the end of the five-year lease term, the Lenders agree to sell such equipment back to the JV Company for a nominal amount (RMB 1). The JV Company’s obligations under the Lease Financing are secured by the land and building owned by the JV Company (the “Collateral”). The proceeds from the Lease Financing were used primarily for the acquisition and installation of the 12-inch fabrication equipment and other expenses of the JV Company relating to the completion of the fabrication facility located in Chongqing. The Agreements contain customary representation, warranties and covenants, including restrictions on the transfer of the Collateral. The Agreements also contain customary events of default, including but not limited to, failure to make payments and breach of material terms under the Agreements. The Agreements include certain customary closing conditions, including the payment of deposit by the JV Company. On June 28, 2020, the parties entered into a modification to this agreement, pursuant to which the interest rate was changed to be the five-year loan prime rate in China plus 0.8125%, or 5.4625%. Other terms of this agreement remain the same. As of December 31, 2020, the outstanding balance of the Lease Financ ing of 244.0 million RMB (equivalent of $37.4 million based on the currency exchange rate as of December 31, 2020) was recorded under short-term and long-term finance lease liabilities. See future minimum lease payment table for finance lease liabilities in Note 6. Long-term debt On April 26, 2020, the JV Company entered into a loan agreement with China Development Bank, Agricultural Bank of China, China Merchants Bank and Chongqing Rural Commercial Bank (collectively, "the Banks") in the aggregate principal amount of RMB 250 million (approximately $35.7 million based on the currency exchange rate between RMB and U.S. Dollar on April 26, 2020). The obligation under the loan agreement is secured by certain assets of the JV Company. Beginning December 18, 2020, the JV Company is required to make consecutive semi-annual payments of principal until December 8, 2024. Interest payments are due on March 20, June 20, September 20 and December 20 of each year based o n the LPR pl us 1.3%. The JV Company drew down RMB 250 million (approximately $35.3 million based on the currency exchange rate between RMB and U.S. Dollar on June 30, 2020) in April 2020. As of December 31, 2020, the outstanding balance of the loan was $36.0 million. In December 2019, the JV Company entered into a loan agreement with China Development Bank in the amount of $24.0 million. The obligation under the loan agreement is secured by certain assets of the JV Company. Beginning December 18, 2020, the JV Company will make consecutive semi-annual payments of principal until December 8, 2024. The interest is accrued based on the LIBOR rate plus 2.8%. The interest is required to be paid on March 21 and September 21 each year. As of December 31, 2020, the outstanding balance of the loan was $21.6 million. On March 12, 2019, the JV Company entered into a loan agreement with The Export-Import Bank of China in the aggregate principal amount of RMB 200 million (approximately $29.8 million based on currency exchange rate between RMB and U.S. Dollar on March 31, 2019). The loan will mature on February 20, 2025. The JV Company drew down RMB 190 million and RMB 10 million in March 2019 and December 2019, respectively. The loan withdraw window expired on February 28, 2020. The interest is accrued based on the China Base Rate multiplied by 1.1, or 5.39%. The loan requires quarterly interest payments. The principal payments are required to be paid every 6 months over the term of loan commencing in October 2019. This loan is secured by the buildings and certain equipment owned by the JV Company. As a condition of the loan arrangement, 14 million RMB (approximately $2.0 million) of cash is held as restricted cash by the JV Company as a compensating balance at the bank until the principal is paid. On June 24, 2020, a modification of this loan was signed, pursuant to which the interest rate was changed to be based on the five-year loan prime rate in China plus 0.74%, or 5.39%. Other terms of this loan remain the same. As of December 31, 2020, the outstanding balance of the loan was 189 million RMB (equivalent of $28.9 million b ased on the currency exchange rate as of December 31, 2020). On May 1, 2018, Jireh Semiconductor Incorporated ("Jireh"), a wholly-owned subsidiary of the Company, entered into a loan agreement with a financial institution (the "Bank") that provided a term loan in the amount of $17.8 million. The obligation under the loan agreement is secured by certain real estate assets of Jireh and guaranteed by the Company. The loan has a five-year term and matures on June 1, 2023. Beginning June 1, 2018, Jireh made consecutive monthly payments of principal and interest to the Bank. The outstanding principal accrues interest at a fixed rate of 5.04% per annum on the basis of a 360-day year. The loan agreement contains customary restrictive covenants and includes certain financial covenants that require the Company to maintain, on a consolidated basis, specified financial ratios. The Company was in compliance with these covenants as of December 31, 2020. As of December 31, 2020, the outstanding balance of the term loan w as $15.5 million. On August 15, 2017, Jireh entered into a credit agreement with the Bank that provided a term loan in an amount up to $30.0 million for the purpose of purchasing certain equipment for the Company's fabrication facility located in Oregon. The obligation under the credit agreement is secured by substantially all assets of Jireh and guaranteed by the Company. The credit agreement has a five-year term and matures on August 15, 2022. In January 2018 and July 2018, Jireh drew down the loan in the amount of $13.2 million and $16.7 million, respectively. Beginning in October 2018, Jireh is required to pay to the Bank on each payment date, the outstanding principal amount of the loan in monthly installments. The loan accrues interest based on an adjusted LIBOR as defined in the credit agreement, plus a specified applicable margin in the range of 1.75% to 2.25%, based on the outstanding balance of the loan. The credit agreement contains customary restrictive covenants and includes certain financial covenants that require the Company to maintain, on a consolidated basis, specified financial ratios and fixed charge coverage ratio. The Company was in compliance with these covenants as of December 31, 2020. As of December 31, 2020, the outstanding balance of the term loan w as $13.0 million. Maturities of short-term debt and long-term debt were as follows (in thousands): Year ending June 30, 2021 (Remaining) $ 24,784 2022 35,127 2023 38,256 2024 24,125 2025 15,566 Total principal 137,858 Less: debt issuance costs (1,188) Total principal, less debt issuance costs $ 136,670 Short-term Debt Long-term Debt Principal amount $ 44,060 $ 93,798 Less: debt issuance costs (486) (702) Total debt, less debt issuance costs $ 43,574 $ 93,096

Leases

Leases	6 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Leases	Leases The Company evaluates contracts for lease accounting at contract inception and assesses lease classification at the lease commencement date. Operating leases are included in operating lease right-of-use ("ROU") assets, operating lease liabilities and operating lease liabilities - long-term on the Company's condensed consolidated balance sheets. Finance leases are included in property, plant and equipment, finance lease liabilities and finance lease liabilities-long-term on the condensed consolidated balance sheets. The Company recognizes a ROU asset and corresponding lease obligation liability at the lease commencement date where the lease obligation liability is measured at the present value of the minimum lease payments. As most of the leases do not provide an implicit rate, the Company uses its incremental borrowing rate at lease commencement. The Company uses an interest rate commensurate with the interest rate to borrow on a collateralized basis over a similar term with an amount equal to the lease payments. Operating leases are primarily related to offices, research and development facilities, sales and marketing facilities, and manufacturing facilities. In addition, long-term supply agreements to lease gas tank equipment and purchase industrial gases are accounted for as operating leases. Lease agreements frequently include renewal provisions and require the Company to pay real estate taxes, insurance and maintenance costs. For operating leases, the amortization of the ROU asset and the accretion of its lease obligation liability result in a single straight-line expense recognized over the lease term. The finance lease is related to the RMB 400.0 million of lease financing of the JV Company with YinHai Leasing Company and The Export-Import Bank of China. See Note 5 - Bank Borrowings for details. The Company does not record leases on the condensed consolidated balance sheets with a term of one year or less. The components of the Company’s operating and finance lease expenses are as follows for the periods presented (in thousands): Six Months Ended December 31, 2020 2019 Operating Leases: Fixed rent expense $ 3,407 $ 2,614 Variable rent expense 419 421 Finance Lease: Amortization of equipment 1,149 1,716 Interest 1,187 1,457 Short-term leases Short-term lease expenses 107 152 Total lease expenses $ 6,269 $ 6,360 Supplemental balance sheets information related to the Company’s operating and finance leases is as follows (in thousands, except lease term and discount rate): December 31, June 30, Operating Leases : ROU assets associated with operating leases $ 34,395 $ 32,948 Finance Lease: Property, plant and equipment, gross $ 113,108 $ 104,374 Accumulated depreciation (94,607) (86,540) Property, plant and equipment, net $ 18,501 $ 17,834 Weighted average remaining lease term (in years) Operating leases 8.87 9.57 Finance lease 2.22 2.72 Weighted average discount rate Operating leases 4.50 % 4.45 % Finance lease 5.46 % 5.46 % Supplemental cash flow information related to the Company’s operating and finance lease is as follows (in thousands): Six Months Ended December 31, 2020 2019 Cash paid from amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 3,341 $ 2,541 Operating cash flows from finance lease $ 1,187 $ 1,457 Financing cash flows from finance lease $ 8,119 $ 3,403 Non-cash investing and financing information: Operating lease right-of-use assets obtained in exchange for lease obligations $ 2,824 $ 16,088 Future minimum lease payments are as follows as of December 31, 2020 (in thousands): Operating Leases Finance Leases The remainder of fiscal 2021 $ 3,088 $ 9,241 2022 6,697 17,803 2023 5,561 12,904 2024 4,292 — 2025 3,617 — Thereafter 21,458 — Total minimum lease payments 44,713 39,948 Less amount representing interest (8,715) (2,592) Total lease liabilities $ 35,998 $ 37,356
Leases	Leases The Company evaluates contracts for lease accounting at contract inception and assesses lease classification at the lease commencement date. Operating leases are included in operating lease right-of-use ("ROU") assets, operating lease liabilities and operating lease liabilities - long-term on the Company's condensed consolidated balance sheets. Finance leases are included in property, plant and equipment, finance lease liabilities and finance lease liabilities-long-term on the condensed consolidated balance sheets. The Company recognizes a ROU asset and corresponding lease obligation liability at the lease commencement date where the lease obligation liability is measured at the present value of the minimum lease payments. As most of the leases do not provide an implicit rate, the Company uses its incremental borrowing rate at lease commencement. The Company uses an interest rate commensurate with the interest rate to borrow on a collateralized basis over a similar term with an amount equal to the lease payments. Operating leases are primarily related to offices, research and development facilities, sales and marketing facilities, and manufacturing facilities. In addition, long-term supply agreements to lease gas tank equipment and purchase industrial gases are accounted for as operating leases. Lease agreements frequently include renewal provisions and require the Company to pay real estate taxes, insurance and maintenance costs. For operating leases, the amortization of the ROU asset and the accretion of its lease obligation liability result in a single straight-line expense recognized over the lease term. The finance lease is related to the RMB 400.0 million of lease financing of the JV Company with YinHai Leasing Company and The Export-Import Bank of China. See Note 5 - Bank Borrowings for details. The Company does not record leases on the condensed consolidated balance sheets with a term of one year or less. The components of the Company’s operating and finance lease expenses are as follows for the periods presented (in thousands): Six Months Ended December 31, 2020 2019 Operating Leases: Fixed rent expense $ 3,407 $ 2,614 Variable rent expense 419 421 Finance Lease: Amortization of equipment 1,149 1,716 Interest 1,187 1,457 Short-term leases Short-term lease expenses 107 152 Total lease expenses $ 6,269 $ 6,360 Supplemental balance sheets information related to the Company’s operating and finance leases is as follows (in thousands, except lease term and discount rate): December 31, June 30, Operating Leases : ROU assets associated with operating leases $ 34,395 $ 32,948 Finance Lease: Property, plant and equipment, gross $ 113,108 $ 104,374 Accumulated depreciation (94,607) (86,540) Property, plant and equipment, net $ 18,501 $ 17,834 Weighted average remaining lease term (in years) Operating leases 8.87 9.57 Finance lease 2.22 2.72 Weighted average discount rate Operating leases 4.50 % 4.45 % Finance lease 5.46 % 5.46 % Supplemental cash flow information related to the Company’s operating and finance lease is as follows (in thousands): Six Months Ended December 31, 2020 2019 Cash paid from amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 3,341 $ 2,541 Operating cash flows from finance lease $ 1,187 $ 1,457 Financing cash flows from finance lease $ 8,119 $ 3,403 Non-cash investing and financing information: Operating lease right-of-use assets obtained in exchange for lease obligations $ 2,824 $ 16,088 Future minimum lease payments are as follows as of December 31, 2020 (in thousands): Operating Leases Finance Leases The remainder of fiscal 2021 $ 3,088 $ 9,241 2022 6,697 17,803 2023 5,561 12,904 2024 4,292 — 2025 3,617 — Thereafter 21,458 — Total minimum lease payments 44,713 39,948 Less amount representing interest (8,715) (2,592) Total lease liabilities $ 35,998 $ 37,356

Shareholders' Equity and Share-

Shareholders' Equity and Share-based Compensation	6 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement, Noncash Expense [Abstract]
Shareholders' Equity and Share-based Compensation	Shareholders' Equity and Share-based Compensation Share Repurchase In September 2017, the Board of Directors approved a repurchase program (the “Repurchase Program”) that allowed the Company to repurchase its common shares from the open market pursuant to a pre-established Rule 10b5-1 trading plan or through privately negotiated transactions up to an aggregate of $30.0 million. The amount and timing of any repurchases under the Repurchase Program depend on a number of factors, including but not limited to, the trading price, volume and availability of the Company's common shares. Shares repurchased under this program are accounted for as treasury shares and the total cost of shares repurchased is recorded as a reduction of shareholders' equity. From time to time, treasury shares may be reissued as part of the Company's share-based compensation programs. Gains on re-issuance of treasury stock are credited to additional paid-in capital; losses are charged to additional paid-in capital to offset the net gains, if any, from previous sales or re-issuance of treasury stock. Any remaining balance of the losses is charged to retained earnings. During the six months ended December 31, 2020, the Company did not repurchase any shares pursuant to the Repurchase Program. Since the inception of the program, the Company repurchased an aggregate of 6,784,648 shares for a total cost of $67.3 million, at an average price of $9.92 per share, excluding fees and related expenses. No repurchased shares have been retired. Of the 6,784,648 repurchased shares, 155,670 shar es with a weighted average repurchase price o f $10.19 per share, were reissued at an average price of $5.37 p er share pursuant to option exercises and vested restricted share units ("RSU"). As of December 31, 2020, approximately $13.4 million remained available under the Repurchase Program. Time-based Restricted Stock Units ("TRSU") The following table summarizes the Company's TRSU activities for the six months ended December 31, 2020: Number of Restricted Stock Weighted Average Weighted Average Aggregate Intrinsic Value Nonvested at June 30, 2020 932,138 $ 11.36 1.66 $ 10,141,661 Granted 211,635 $ 17.70 Vested (181,460) $ 16.27 Forfeited (13,375) $ 10.47 Nonvested at December 31, 2020 948,938 $ 11.85 1.29 $ 22,432,894 Market-based Restricted Stock Units ("MSUs") During the quarter ended September 30, 2018, the Company granted 1.3 million market-based restricted stock units ("MSUs") to certain personnel. The number of shares to be earned at the end of performance period is determined based on the Company’s achievement of specified stock prices and revenue thresholds during the performance period from January 1, 2019 to December 31, 2021 as well as the recipients remaining in continuous service with the Company through such period. The MSUs vest in four equal annual installments after the end of each performance period. The Company estimated the grant date fair values of its MSUs using a Monte-Carlo simulation model. On August 31, 2020, the Compensation Committee of the Board approved a modification of the terms of MSU to (i) extend the performance period through December 31, 2022 and (ii) change the commencement date for the four-year time-based service period to January 1, 2023. The fair value of these MSUs was recalculated to reflect the change as of August 31, 2020 and the unrecognized compensation amount was adjusted to reflect the increase in fair value. The incremental expenses for the three and six months ended December 31, 2020 were immaterial. The Company recorded approximatel y $0.4 million and $0.6 million of expenses for MSUs during the three and six months ended December 31, 2020, respectively, and approximately $0.1 million and $0.3 million during the three and six months ended December 31, 2019, respectively. Performance-based Restricted Stock Units ("PRSUs") In March each year since year 2017, the Company granted performance-based RSUs (“PRSUs”) to certain personnel. The number of shares to be earned under the PRSUs is determined based on the level of attainment of predetermined financial goals. The PRSUs vest in four equal annual installments from the first anniversary date after the grant date if certain predetermined financial goals were met. The Company recorded approximately $0.4 million and $0.8 million o f expense for these PRSUs during the three and six months ended December 31, 2020, respectively, and approximately $0.5 million and $0.7 million during the three and six months ended December 31, 2019, respectively. During the three months ended June 30, 2019, the Company announced an incentive program. Under this program, each participant’s award is denominated in stock and subject to achievement of certain objective goals within certain timelines. In June 2020, the Company believed it was most likely that predetermined goal measures would be met. Therefore, started June 2020 quarter the Company recorded $0.6 million of non-cash compensation expense each quarter for these awards. The expense was reported in the other current liabilities line on the condensed consolidated balance sheets as the amount of bonus is to be settled in variable number of RSU’s at the completion of the objective goals. Such non-cash compensation expense was recorded as part of share-based compensation expense in the condensed consolidated statements of operations. During the three and six months ended December 31, 2020, the Company granted RSUs valued at $1.0 million and $2.0 million, respectively, to participants, which were fully vested due to achievement of certain objective measures. The following table summarizes the Company's PRSUs activities for the six months ended December 31, 2020: Number of Performance-based Restricted Stock Weighted Average Weighted Average Aggregate Intrinsic Value Nonvested at June 30, 2020 342,775 $ 12.38 1.60 $ 3,729,392 Forfeited (1,750) $ 16.61 Nonvested at December 31, 2020 341,025 $ 12.36 1.09 $ 8,061,831 Stock Options The Company did not grant any stock options during the three and six months ended December 31, 2020 and 2019. The following table summarizes the Company's stock option activities for the six months ended December 31, 2020: Weighted Weighted Average Average Remaining Number of Exercise Price Contractual Aggregate Shares Per Share Term (in years) Intrinsic Value Outstanding at June 30, 2020 643,978 $ 8.79 2.89 $ 1,544,664 Exercised (134,559) $ 11.60 Outstanding at December 31, 2020 509,419 $ 8.05 2.81 $ 7,940,606 Options vested and expected to vest 509,419 $ 8.05 2.81 $ 7,940,606 Exercisable at December 31, 2020 509,419 $ 8.05 2.81 $ 7,940,606 Employee Share Purchase Plan ("ESPP") The assumptions used to estimate the fair values of common shares issued under the ESPP were as follows: Six Months Ended December 31, 2020 Volatility rate 63.1% Risk-free interest rate 0.2% Expected term 1.3 years Dividend yield 0% Share-based Compensation Expense T he total share-based compensation expense recognized in the condensed consolidated statements of operations for the periods presented was as follows: Three Months Ended December 31, Six Months Ended December 31, 2020 2019 2020 2019 (in thousands) (in thousands) Cost of goods sold $ 383 $ 404 $ 768 $ 840 Research and development 1,243 472 2,323 996 Selling, general and administrative 1,598 1,611 3,009 3,020 $ 3,224 $ 2,487 $ 6,100 $ 4,856 As of December 31, 2020, total unrecognized compensation cost under the Company's equity plans was $12.4 million, which is expected to be recognized over a weighted-average period of 2.4 years.

Income Taxes

Income Taxes	6 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company recognized income tax expense of approximately $0.7 million and $0.6 million for the three months ended December 31, 2020 and 2019, respectively. The income tax expense of $0.7 million for the three months ended December 31, 2020 included a $0.01 million discrete tax expense. The income tax expense of $0.6 million for the three months ended December 31, 2019 included a $0.01 million discrete tax expense. Excluding the discrete income tax items, the effective tax rate for the three months ended December 31, 2020 and 2019 was 5.0% and (13.8)%, respectively. The changes in the effective tax rate and tax expense between the periods resulted primarily from the Company reporting pretax book income of $13.2 million for the three months ended December 31, 2020 as compared to a pretax book loss of $4.0 million for the three months ended December 31, 2019. The Company recognized income tax expense of approximately $1.7 million and $1.0 million for the six months ended December 31, 2020 and 2019, respectively. The income tax expense of $1.7 million for the six months ended December 31, 2020 included a $0.02 million discrete tax benefit. The income tax expense of $1.0 million for the six months ended December 31, 2019 included a $0.03 million discrete tax expense. Excluding the discrete income tax items, the effective tax rate for the six months ended December 31, 2020 and 2019 was 7.4% and (17.4)%, respectively. The changes in the effective tax rate and tax expense between the periods resulted primarily from the Company reporting pretax book income of $23.0 million for the six months ended December 31, 2020 as compared to a pretax book loss of $5.5 million for the six months ended December 31, 2019. The Company files its income tax returns in the United States and in various foreign jurisdictions. The tax years 2001 to 2020 remain open to examination by U.S. federal and state tax authorities. The tax years 2013 to 2020 remain open to examination by foreign tax authorities. The Company's income tax returns are subject to examinations by the Internal Revenue Service and other tax authorities in various jurisdictions. In accordance with the guidance on the accounting for uncertainty in income taxes, the Company regularly assesses the likelihood of adverse outcomes resulting from these examinations to determine the adequacy of its provision for income taxes. These assessments can require considerable estimates and judgments. As of December 31, 2020, the gross amount of unrecognized tax benefits was approximately $7.2 million, of which $4.3 million , if recognized, would reduce the effective income tax rate in future periods. If the Company's estimate of income tax liabilities proves to be less than the ultimate assessment, then a further charge to expense would be required. If events occur and the payment of these amounts ultimately proves to be unnecessary, the reversal of the liabilities would result in tax benefits being recognized in the period when the Company determines the liabilities are no longer necessary. The Company does not anticipate any material changes to its uncertain tax positions during the next twelve months. "U.S. Coronavirus Aid, Relief and Economic Security Act” (“CARES Act”), Enacted March 27, 2020 On March 27, 2020, the United States enacted the Coronavirus Aid, Relief and Economic Security Act (“the CARES Act”), which made the changes to existing U.S. tax laws, including, but not limited to, (1) allowing U.S. federal net operating losses originated in the 2018, 2019 or 2020 tax years to be carried back five years to recover taxes paid based upon taxable income in the prior five years, (2) eliminating the 80% of taxable income limitation on net operating losses for the 2018, 2019 and 2020 tax years (the 80% limitation will be reinstated for tax years after 2020), (3) accelerating the refund of prior year alternative minimum tax credits, (4) modifying the bonus depreciation for qualified improvement property and (5) modifying the limitation on deductible interest expense. As a result of the ability to carryback net operating losses from the June 2018 and June 2019 years to the June 2015 to June 2017 tax years, net operating losses which were previously tax-effected using the current 21% U.S. federal tax rate were revalued to the U.S. tax rates in effect for the June 2015 to June 2017 tax years due to the ability of receiving tax refunds for the taxes paid in these years. Accordingly, the Company reported a discrete tax benefit of $1.1 million in the quarter ended March 31, 2020 related to the re-measurement of the net operating losses that could be realized via the new net operating loss carryback provisions. “U.S. Consolidated Appropriations Act, 2021” (“CAA 2021”), Enacted December 27, 2020 On December 27, 2020, the United States enacted the Consolidated Appropriations Act, 2021, which made changes to existing U.S. tax laws. There was no material impact of the tax law changes included in the Consolidated Appropriations Act, 2021 to the Company. On July 27, 2015, in Altera Corp. v. Commissioner, the U.S. Tax Court issued an opinion related to the treatment of stock-based compensation expense in an intercompany cost-sharing arrangement. In the July 2015 ruling, the Tax Court concluded that the sharing of the cost of employee stock compensation in a company’s cost-sharing arrangement was invalid under the U.S. Administrative Procedures Act. In June 2019, a panel of the Ninth Circuit of the U.S. Court of Appeals reversed this decision. In July 2019, Altera petitioned U.S. Court of Appeals for the Ninth Circuit to hold an en banc rehearing of the case. The petition was subsequently denied by the Ninth Circuit. Altera appealed the case to the U.S. Supreme Court in February 2020, but the U.S. Supreme Court declined to hear the case in June 2020, leaving intact the U.S. Court of Appeals for the Ninth Circuit’s decision. AOS has not recorded any benefit related to the Altera Corporation Tax Court decision in any period through December 2020. The Company will continue to monitor ongoing developments and potential impact to its financial statements.

Segment and Geographic Informat

Segment and Geographic Information	6 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Segment and Geographic Information	Segment and Geographic Information The Company is organized as, and operates in, one operating segment: the design, development and supply of power semiconductor products for computing, consumer electronics, communication and industrial applications. The chief operating decision-maker is the Chief Executive Officer. The financial information presented to the Company's Chief Executive Officer is on a consolidated basis, accompanied by information about revenue by customer and geographic region, for purposes of evaluating financial performance and allocating resources. The Company has one business segment, and there are no segment managers who are held accountable for operations, operating results and plans for products or components below the consolidated unit level. Accordingly, the Company reports as a single operating segment. The Company sells its products primarily to distributors in the Asia Pacific region, who in turn sell these products to end customers. Because the Company's distributors sell their products to end customers which may have a global presence, revenue by geographical location is not necessarily representative of the geographical distribution of sales to end user markets. The revenue by geographical location in the following tables is based on the country or region in which the products were shipped to: Three Months Ended December 31, Six Months Ended December 31, 2020 2019 2020 2019 (in thousands) (in thousands) Hong Kong $ 134,506 $ 97,244 $ 261,106 $ 190,346 China 22,851 16,571 46,060 33,083 South Korea 146 2,279 282 8,269 United States 1,139 898 2,595 1,999 Other countries 188 868 338 1,965 $ 158,830 $ 117,860 $ 310,381 $ 235,662 The following is a summary of revenue by product type: Three Months Ended December 31, Six Months Ended December 31, 2020 2019 2020 2019 (in thousands) (in thousands) Power discrete $ 118,500 $ 99,321 * $ 232,872 $ 198,001 * Power IC 37,381 16,825 71,839 34,410 Packaging and testing services 2,949 1,714 5,670 3,251 $ 158,830 $ 117,860 $ 310,381 $ 235,662 * Certain products were reclassified from power discrete to Power IC. Long-lived assets, net consisting of property, plant and equipment and land use rights, by geographical area are as follows: December 31, June 30, (in thousands) China $ 329,404 $ 310,600 United States 100,672 100,984 Other countries 732 756 $ 430,808 $ 412,340

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Purchase Commitments As of December 31, 2020 and June 30, 2020, the Company had approximately $45.6 million and $43.9 million, respectively, of outstanding purchase commitments primarily for purchases of semiconductor raw materia ls, wafers, spare parts, packaging and testing services and others. As of December 31, 2020 and June 30, 2020, the Company had approximate ly $38.1 million a nd $18.0 million, primarily for the JV Company, respectively, of capital commitments for the purchase of property and equipment. Other Commitments See Note 1, Note 5 and Note 6 of the Notes to the Condensed Consolidated Financial Statements contained in this Quarterly Report on Form 10-Q for descriptions of commitments including Joint Venture, bank borrowings and leases. Contingencies and Indemnities The Company has in the past, and may from time to time in the future, become involved in legal proceedings arising from the normal course of business activities. The semiconductor industry is characterized by frequent claims and litigation, including claims regarding patent and other intellectual property rights as well as improper hiring practices. Irrespective of the validity of such claims, the Company could incur significant costs in the defense of such claims and suffer adverse effects on its operations. In December 2019, the U.S. Department of Justice ("DOJ") commenced an investigation into the Company's compliance with export control regulations relating to its business transactions with Huawei and its affiliates (“Huawei”), which were added to the “Entity List” maintained by the Department of Commerce (“DOC”) on May 16, 2019. The Company is cooperating fully with federal authorities in the investigation, including responding to requests for documents and information from DOJ in connection with the investigation. The Company has maintained an export control compliance program and has been committed to comply fully with all applicable laws and regulations. In connection with this investigation, DOC requested the Company to suspend shipments of its products to Huawei, and the Company complied with such request, and the Company has not shipped any product to Huawei after December 31, 2019 (see Note 3). The Company is currently working with DOC to resolve this issue. Given the case is in still ongoing and neither DOJ nor DOC have provided the Company with any clear indication of the timing and schedule for the investigation, the Company cannot estimate the reasonably possible loss or range of loss that may occur. Also, the Company is unable to predict the duration, scope, result or related costs of the investigation, although the Company expects to incur additional professional fees as a result of this matter. In addition, the Company is unable to predict what, if any, further action that may be taken by the government in connection with the investigation, or what, if any, penalties, sanctions or remedial actions may be sought. On March 19, 2020, Darryl Gray, a stockholder of the Company (the “Plaintiff”), filed a putative class action complaint in the United States District Court for the Southern District of New York (the “Gray Action”), alleging that the Company and its management members made material misstatements or omissions regarding the Company’s business and operations, including its export control practices relating to business transactions with Huawei and its affiliate. The Gray Action asserts claims under Section 10(b) of the Exchange Act against the Company, its Chief Executive Officer and Chief Financial Officer (collectively, the Defendants”), as well as claims under Section 20(a) of the Exchange Act against the Chief Executive Officer and Chief Financial Officer. Among other remedies, the Gray Action seeks to recover compensatory and other damages as well as attorney’s fees and costs. On May 18, 2020, Plaintiff moved for an order appointing him as Lead Plaintiff pursuant to Section 21D of the Exchange Act and approving Glancy Prongay & Murray LLP as Lead Counsel for the putative class (the “Motion”). On July 1, 2020, the Court entered an order granting the Motion and requiring that: (i) Lead Plaintiff file an amended complaint or designate the current complaint as operative within sixty days; (ii) Defendants answer the complaint or otherwise move within sixty days of such filing or designation; (iii) Lead Plaintiff file an opposition, if any, within forty-five days; and (iv) Defendants file a reply, if any, forty-five days thereafter. On August 28, 2020, Plaintiff filed an amended complaint asserting the same claims against the Defendants, and adding the Company’s Executive Vice President of Product Line as a defendant on both claims. On October 27, 2020, the Defendants moved to dismiss the action in its entirety. Plaintiff filed his opposition on December 11, 2020 and Defendants filed their reply brief on January 25, 2021. The Company believes the claims in the Gray Action are without merit and intends to vigorously defend this litigation. Given the case is in its early stages and still on going, the Company cannot estimate the reasonably possible loss or range of loss that may occur. The Company is a party to a variety of agreements that it has contracted with various third parties. Pursuant to these agreements, the Company may be obligated to indemnify another party to such an agreement with respect to certain matters. Typically, these obligations arise in the context of contracts entered into by the Company, under which the Company customarily agrees to hold the other party harmless against losses arising from a breach of representations and covenants related to such matters as title to assets sold, certain intellectual property rights, specified environmental matters and certain income taxes. In these circumstances, payment by the Company is customarily conditioned on the other party making a claim pursuant to the procedures specified in the particular contract, which procedures typically allow the Company to challenge the other party's claim. Further, the Company's obligations under these agreements may be limited in time and/or amount, and in some instances, the Company may have recourse against third parties for certain payments made by it under these agreements. The Company has not historically paid or recorded any material indemnifications, and no accrual was made at December 31, 2020 and June 30, 2020. The Company has agreed to indemnify its directors and certain employees as permitted by law and pursuant to its Bye-laws, and has entered into indemnification agreements with its directors and executive officers. The Company has not recorded a liability associated with these indemnification arrangements, as it historically has not incurred any material costs associated with such indemnification obligations. Costs associated with such indemnification obligations may be mitigated by insurance coverage that the Company maintains. However, such insurance may not cover any, or may cover only a portion of, the amounts the Company may be required to pay. In addition, the Company may not be able to maintain such insurance coverage in the future.

The Company and Significant A_2

The Company and Significant Accounting Policies (Policies)	6 Months Ended
	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Preparation	Basis of Preparation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) for interim financial information and with the instructions to Article 10 of Securities and Exchange Commission Regulation S-X, as amended. They do not include all information and footnotes necessary for a fair presentation of financial position, results of operations and cash flows in conformity with U.S. GAAP for complete financial statements. These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and related notes contained in the Company’s Annual Report on Form 10-K for the fiscal year ended June 30, 2020. All significant intercompany balances and transactions have been eliminated in consolidation. In the opinion of management, all adjustments (consisting of normal recurring adjustments and accruals) considered necessary for a fair presentation of the results of operations for the periods presented have been included in the interim periods. Operating results for the three and six months ended December 31, 2020 are not necessarily indicative of the results that may be expected for the fiscal year ending June 30, 2021 or any other interim period. The condensed consolidated balance sheets at June 30, 2020 is derived from the audited financial statements included in the Company’s Annual Report on Form 10-K for the fiscal year ended June 30, 2020. Reclassification The Company has reclassified certain amounts previously reported in its financial statements to conform to the current presentation. These reclassifications did not have a material impact on our consolidated financial statements.
Joint Venture	The Joint Venture is accounted under the provisions of the consolidation guidance since the Company has controlling financial interest.
Risks and Uncertainties	Certain Significant Risks and Uncertainties Related to Outbreak of Coronavirus Disease 2019 (“COVID-19”) The COVID-19 pandemic has had and continues to have a negative impact on business and economic activities across the globe. As a result of the COVID-19 pandemic and the global economic downturn and changing consumer behaviors due to various restrictions imposed by governments, the Company has experienced shifting market trends, including an increasing demand in the markets for notebooks, PCs and gaming devices and decreasing demand for mobile phone and industrial products, as more consumers are staying at and working from home. While the Company has recently benefited from the
Use of Estimates	Use of Estimates The preparation of the condensed consolidated financial statements in conformity with U.S. GAAP requires the Company to make estimates, judgments and assumptions that affect the reported amounts of assets, liabilities, revenue and expenses. To the extent there are material differences between these estimates and actual results, the Company's condensed consolidated financial statements will be affected. On an ongoing basis, the Company evaluates the estimates, judgments and assumptions including those related to stock rotation returns, price adjustments, allowance for doubtful accounts, inventory reserves, warranty accrual, income taxes, leases, share-based compensation, recoverability of and useful lives for property, plant and equipment and intangible assets, as well as the economic implications of the COVID-19 pandemic.
Leases	Leases The Company determines if an arrangement is a lease at inception. Operating leases are included in operating lease right-of-use ("ROU") assets, current operating lease liabilities and long-term operating lease liabilities on the Company's condensed consolidated balance sheets. Finance leases are included in property, plant and equipment, current finance lease liabilities and long-term finance leases liabilities on the condensed consolidated balance sheets.
Revenue recognition	Revenue recognition The Company determines revenue recognition through the following steps: (1) identification of the contract with a customer; (2) identification of the performance obligations in the contract; (3) determination of the transaction price; (4) allocation of the transaction price to the performance obligations in the contract; and (5) recognition of revenue when, or as, a performance obligation is satisfied. The Company recognizes revenue when product is shipped to the customer, net of estimated stock rotation returns and price adjustments to certain distributors.
Share-based Compensation Expense	Share-based Compensation Expense The Company maintains an equity-settled, share-based compensation plan to grant restricted share units and stock options. The Company recognizes expense related to share-based compensation awards that are ultimately expected to vest based on estimated fair values on the date of grant. The fair value of restricted share units is based on the fair value of the Company's common share on the date of grant. For restricted stock awards subject to market conditions, the fair value of each restricted stock award is estimated at the date of grant using the Monte-Carlo pricing model. The fair value of stock options is estimated
Restricted Cash	Restricted CashAs a condition of the loan agreement, the Company is required to keep a compensating balance at the issuing bank (see Note 5). In addition, the Company maintains restricted cash in connection with cash balances temporarily restricted for regular business operations including the possibility of a dispute with a vendor. These balances have been excluded from the Company’s cash and cash equivalents balance and are classified as restricted cash in the Company’s condensed consolidated balance sheets.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The fair value of cash equivalents is categorized in Level 1 in the fair value hierarchy. Cash equivalents consist primarily of short-term bank deposits. The carrying values of financial instruments such as cash and cash equivalents, accounts receivable and accounts payable approximate their carrying values due to their short-term maturities. The carrying value of the company's debt is considered a reasonable estimate of fair value which is estimated by considering the current rates available to the Company for debt of the same remaining maturities, structure, credit risk and terms of the debts.
Government Grants	Government GrantsThe Company occasionally receives government grants that provide financial assistance for certain eligible expenditures in China. These grants include reimbursements on interest expense on bank borrowings, payroll tax credits, credit for property, plant and equipment in a particular geographical location, employment credits, as well as business expansion credits. Government grants are not recognized until there is reasonable assurance that the Company will comply with the conditions attaching to it, and that the grant will be received. The Company records such grants either as a reduction of the related expense, a reduction of the cost of the related asset, or as other income depending upon the nature of the grant.
Long-lived Assets	Long-lived AssetsThe Company evaluates its long-lived assets for impairment whenever events or changes indicate that the carrying amount of such assets may not be recoverable. Due to the COVID-19 pandemic, the Company assessed the changes in circumstances that occurred since the March 2020 quarter. These factors included operating losses, a decrease in the Company's share price in February and March of 2020, which reduced its market capitalization, expectation of lower business growth for the coming quarters, increased and prolonged economic and regulatory uncertainty in the global economies, and the expectation of higher supply chain costs and increased competition. Therefore, the Company performed a recoverability test by comparing the sum of the estimated undiscounted future cash flows of its long-lived assets to their carrying amount as of June 30, 2020. Some of the more significant assumptions used in the estimated future cash flows include net sales, cost of goods sold, operating expenses, working capital, capital expenditures, income tax rates, and long-term growth rates that appropriately reflects the risks inherent in the future cash flow stream. The Company selected the assumptions used in the financial forecasts by referencing to historical data, supplemented by current and anticipated market conditions, estimated product growth rates and management's plans. These estimated future cash flows were consistent with those the Company uses in its internal planning.
Comprehensive Income (Loss)	Comprehensive Income (Loss)Comprehensive income (loss) is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. The Company's accumulated other comprehensive income (loss) consists of cumulative foreign currency translation adjustments. Total comprehensive income (loss) is presented in the condensed consolidated statements of comprehensive income (loss).
Recent Accounting Pronouncements	Recent Accounting Pronouncements Recently Issued Accounting Standards not yet adopted In August 2020, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 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, which, among other things, provides guidance on how to account for contracts on an entity’s own equity. This ASU simplifies the accounting for certain financial instruments with characteristics of liabilities and equity. Specifically, the ASU eliminated the need for the Company to assess whether a contract on the entity’s own equity (1) permits settlement in unregistered shares, (2) whether counterparty rights rank higher than shareholder’s rights, and (3) whether collateral is required. In addition, the ASU requires incremental disclosure related to contracts on the entity’s own equity and clarifies the treatment of certain financial instruments accounted for under this ASU on earnings per share. For public business entities, the ASU is effective for fiscal years beginning after December 15, 2021, and interim periods within those fiscal years. The Company does not expect the adoption of this guidance will have a material impact on its consolidated financial position, results of operations or cash flows. In January 2020, the FASB issued ASU No. 2020-01, “Investments - Equity Securities (Topic 321), Investments - Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815) - Clarifying the Interactions between Topic 321, Topic 323, and Topic 815.” The ASU is based on a consensus of the Emerging Issues Task Force and is expected to increase comparability in accounting for these transactions. ASU 2016-01 made targeted improvements to accounting for financial instruments, including providing an entity the ability to measure certain equity securities without a readily determinable fair value at cost, less any impairment, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. Among other topics, the amendments clarify that an entity should consider observable transactions that require it to either apply or discontinue the equity method of accounting. For public business entities, the amendments in the ASU are effective for fiscal years beginning after December 15, 2020, and interim periods within those fiscal years. The Company does not expect the adoption of this guidance will have a material impact on its consolidated financial position, results of operations or cash flows. In December 2019, the FASB issued ASU No. 2019-12 “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes ("ASU 2019-12") by removing certain exceptions to the general principles. The amendments will be effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. Early adoption of the amendments is permitted. Depending on the amendment, adoption may be applied on a retrospective, modified retrospective or prospective basis. The Company is currently evaluating the impacts of adoption of the new guidance to its consolidated financial statements. Recently Adopted Accounting Standards In August 2018, the FASB issued ASU 2018-15 “Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract". These amendments align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contact with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by these amendments. ASU 2018-15 had no material impact on the Company's consolidated financial statements. In August 2018, the FASB issued ASU 2018-13, “Fair Value Measurement (Topic 820): Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement ("ASU 2018-13”). ASU 2018-13 amends existing fair value measurement disclosure requirements by adding, changing, or removing certain disclosures. The amendments on changes in unrealized gains and losses, the range and weighted average of significant unobservable inputs used to develop Level 3 fair value measurements, and the narrative description of measurement uncertainty should be applied prospectively for only the most recent interim or annual period presented in the initial fiscal year of adoption. All other amendments should be applied retrospectively to all periods presented upon their effective date. ASU 2018-13 had no material impact on the Company's consolidated financial statements. In June 2016, the FASB issued ASU 2016-13, "Financial Instruments - Credit Losses (Topic 326). Topic 326 adds to U.S. GAAP the current expected credit loss ("CECL") model, a measurement model based on expected losses rather than incurred losses. Under this new standard, an entity recognizes its estimate of expected credit losses as an allowance. The new standard is also intended to reduce the complexity of U.S. GAAP by decreasing the number of credit loss models that entities use to account for debt instruments. The new guidance significantly changes the accounting for credit losses. The Company adopted ASU 2016-13 using the modified-retrospective approach in the first quarter of fiscal 2021 with no impact to its condensed consolidated financial statements. The adoption of Topic 326 did not significantly change the Company's approach to the valuation of trade receivables. The Company determines whether there is an expected loss on its accounts receivable by reviewing all available data, including its customers' latest available financial statements, their credit standing and historical collection experience, as well as current and future market and economic conditions. As of December 31, 2020, the allowance for credit losses on the Company's trade receivables remained immaterial.
Concentration of Credit Risk	The Company manages its credit risk associated with exposure to distributors and direct customers on outstanding accounts receivable through the application and review of credit approvals, credit ratings and other monitoring procedures. In some instances, the Company also obtains letters of credit from certain customers. Credit sales, which are mainly on credit terms of 30 to 60 days, are only made to customers who meet the Company's credit requirements, while sales to new customers or customers with low credit ratings are usually made on an advance payment basis. The Company considers its trade accounts receivable to be of good credit quality because its key distributors and direct customers have long-standing business relationships with the Company and the Company has not experienced any significant bad debt write-offs of accounts receivable in the past. The Company closely monitors the aging of accounts receivable from its distributors and direct customers, and regularly reviews their financial positions, where available.

Net Income Per Common Share A_2

Net Income Per Common Share Attributable to Alpha and Omega Semiconductor Limited - (Tables)	6 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The following table presents the calculation of basic and diluted net income (loss) per share attributable to common shareholders: Three Months Ended December 31, Six Months Ended December 31, 2020 2019 2020 2019 (in thousands, except per share data) Numerator: Net income (loss) attributable to Alpha and Omega Semiconductor Limited $ 12,903 $ (1,005) $ 22,477 $ 4 Denominator: Basic: Weighted average number of common shares used to compute basic net income per share 25,672 24,701 25,506 24,620 Diluted: Weighted average number of common shares used to compute basic net income per share 25,672 24,701 25,506 24,620 Effect of potentially dilutive securities: Stock options, RSUs and ESPP shares 1,681 — 1,328 742 Weighted average number of common shares used to compute diluted net income per share 27,353 24,701 26,834 25,362 Net income (loss) per share attributable to Alpha and Omega Semiconductor Limited: Basic $ 0.50 $ (0.04) $ 0.88 $ 0.00 Diluted $ 0.47 $ (0.04) $ 0.84 $ 0.00
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The following potential dilutive securities were excluded from the computation of diluted net income (loss) per share as their effect would have been anti-dilutive: Three Months Ended December 31, Six Months Ended December 31, 2020 2019 2020 2019 (in thousands) (in thousands) Employee stock options and RSUs 7 2,040 66 337 ESPP 35 868 134 597 Total potential dilutive securities 42 2,908 200 934

Concentration of Credit Risk _2

Concentration of Credit Risk and Significant Customers (Tables)	6 Months Ended
	Dec. 31, 2020
Risks and Uncertainties [Abstract]
Schedules of Concentration of Risk, by Risk Factor	Summarized below are individual customers whose revenue or accounts receivable balances were 10% or higher than the respective total consolidated amounts: Three Months Ended December 31, Six Months Ended December 31, Percentage of revenue 2020 2019 2020 2019 Customer A 28.4 % 31.3 % 28.6 % 30.0 % Customer B 36.4 % 37.0 % 34.8 % 36.0 % December 31, June 30, Percentage of accounts receivable Customer A 17.4 % * Customer B 14.4 % * Customer C 23.6 % 29.8 % Customer D 10.0 % * Customer E * 20.1 % Customer F * 10.4 % Customer G * 10.3 % Customer H * 10.9 % * Less than 10%

Balance Sheet Components (Table

Balance Sheet Components (Tables)	6 Months Ended
	Dec. 31, 2020
Balance Sheet Related Disclosures [Abstract]
Schedule of Accounts, Notes, Loans and Financing Receivable	Accounts receivable, net: December 31, June 30, (in thousands) Accounts receivable $ 47,995 $ 43,394 Less: Allowance for price adjustments (23,031) (30,092) Less: Allowance for doubtful accounts (30) (30) Accounts receivable, net $ 24,934 $ 13,272
Schedule of Inventory, Current	Inventories: December 31, June 30, (in thousands) Raw materials $ 58,903 $ 55,377 Work in-process 65,680 61,863 Finished goods 19,724 18,288 $ 144,307 $ 135,528
Other Current Assets	Other current assets: December 31, June 30, (in thousands) VAT receivable $ 2,194 $ 1,639 Other prepaid expenses 2,976 1,900 Prepaid insurance 1,956 1,520 Prepaid maintenance 746 587 Prepayment to supplier 990 938 Prepaid income tax 1,790 1,991 Customs deposit — 163 Other receivables 181 69 $ 10,833 $ 8,807
Property, Plant and Equipment	operty, plant and equipment, net: December 31, June 30, (in thousands) Land $ 4,877 $ 4,877 Building 63,696 58,875 Manufacturing machinery and equipment 493,487 447,079 Equipment and tooling 26,661 25,398 Computer equipment and software 40,004 38,779 Office furniture and equipment 3,744 3,529 Leasehold improvements 73,716 68,224 Land use rights 9,213 8,502 715,398 655,263 Less: accumulated depreciation (324,344) (291,515) 391,054 363,748 Equipment and construction in progress 39,754 48,592 Property, plant and equipment, net $ 430,808 $ 412,340
Intangible Assets Disclosure	Intangible assets, net: December 31, June 30, (in thousands) Patents and technology rights $ 18,037 $ 18,037 Trade name 268 268 Customer relationships 1,150 1,150 19,455 19,455 Less: accumulated amortization (4,634) (2,954) 14,821 16,501 Goodwill 269 269 Intangible assets, net $ 15,090 $ 16,770
Schedule Future Amortization Expense of Intangible Assets	Estimated future minimum amortization expense of intangible assets is as follows (in thousands): Year ending June 30, 2021 (Remaining) $ 1,680 2022 3,360 2023 3,286 2024 3,249 2025 3,246 $ 14,821
Schedule of Other Assets, Noncurrent	Other long-term assets: December 31, June 30, (in thousands) Prepayments for property and equipment $ 1,140 $ 2,242 Investment in a privately held company 100 100 Customs deposit 1,184 1,662 Other long-term deposits 916 850 Office leases deposits 1,103 766 Other 164 184 $ 4,607 $ 5,804
Schedule of Accrued Liabilities	Accrued liabilities: December 31, June 30, (in thousands) Accrued compensation and benefits $ 29,115 $ 19,968 Warranty accrual 767 709 Stock rotation accrual 3,893 3,358 Accrued professional fees 2,678 5,868 Accrued inventory 1,157 775 Accrued facilities related expenses 1,682 1,831 Accrued property, plant and equipment 9,924 11,039 Other accrued expenses 5,757 8,017 Customer deposit 4,663 2,813 ESPP payable 847 608 $ 60,483 $ 54,986
Schedule of Product Warranty Liability	The activities in the warranty accrual, included in accrued liabilities, are as follows: Six Months Ended December 31, 2020 2019 (in thousands) Beginning balance $ 709 $ 623 Additions 239 130 Utilization (181) (102) Ending balance $ 767 $ 651
Stock Rotation Accrual	The activities in the stock rotation accrual, included in accrued liabilities, are as follows: Six Months Ended December 31, 2020 2019 (in thousands) Beginning balance $ 3,358 $ 1,921 Additions 4,180 5,990 Utilization (3,645) (4,075) Ending balance $ 3,893 $ 3,836
Other Long-Term Liabilities	Other long-term liabilities: December 31, June 30, (in thousands) Customer deposits $ 15,000 * $ 8,000 * Computer software liabilities 960 1,897 Equipment liabilities 1,804 — Deferred payroll taxes 2,432 826 Other long-term liabilities $ 20,196 $ 10,723

Bank Borrowing (Tables)

Bank Borrowing (Tables)	6 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Schedule of Maturities	Maturities of short-term debt and long-term debt were as follows (in thousands): Year ending June 30, 2021 (Remaining) $ 24,784 2022 35,127 2023 38,256 2024 24,125 2025 15,566 Total principal 137,858 Less: debt issuance costs (1,188) Total principal, less debt issuance costs $ 136,670 Short-term Debt Long-term Debt Principal amount $ 44,060 $ 93,798 Less: debt issuance costs (486) (702) Total debt, less debt issuance costs $ 43,574 $ 93,096

Leases - (Tables)

Leases - (Tables)	6 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Components of Operating and Finance Lease Costs	The components of the Company’s operating and finance lease expenses are as follows for the periods presented (in thousands): Six Months Ended December 31, 2020 2019 Operating Leases: Fixed rent expense $ 3,407 $ 2,614 Variable rent expense 419 421 Finance Lease: Amortization of equipment 1,149 1,716 Interest 1,187 1,457 Short-term leases Short-term lease expenses 107 152 Total lease expenses $ 6,269 $ 6,360 Supplemental cash flow information related to the Company’s operating and finance lease is as follows (in thousands): Six Months Ended December 31, 2020 2019 Cash paid from amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 3,341 $ 2,541 Operating cash flows from finance lease $ 1,187 $ 1,457 Financing cash flows from finance lease $ 8,119 $ 3,403 Non-cash investing and financing information: Operating lease right-of-use assets obtained in exchange for lease obligations $ 2,824 $ 16,088
Schedule of Lease Assets and Liabilities	Supplemental balance sheets information related to the Company’s operating and finance leases is as follows (in thousands, except lease term and discount rate): December 31, June 30, Operating Leases : ROU assets associated with operating leases $ 34,395 $ 32,948 Finance Lease: Property, plant and equipment, gross $ 113,108 $ 104,374 Accumulated depreciation (94,607) (86,540) Property, plant and equipment, net $ 18,501 $ 17,834 Weighted average remaining lease term (in years) Operating leases 8.87 9.57 Finance lease 2.22 2.72 Weighted average discount rate Operating leases 4.50 % 4.45 % Finance lease 5.46 % 5.46 %
Schedule of Operating Lease Future Minimum Lease Payments (Topic 842)	Future minimum lease payments are as follows as of December 31, 2020 (in thousands): Operating Leases Finance Leases The remainder of fiscal 2021 $ 3,088 $ 9,241 2022 6,697 17,803 2023 5,561 12,904 2024 4,292 — 2025 3,617 — Thereafter 21,458 — Total minimum lease payments 44,713 39,948 Less amount representing interest (8,715) (2,592) Total lease liabilities $ 35,998 $ 37,356
Schedule of Finance Lease Future Minimum Lease Payments (Topic 842)	Future minimum lease payments are as follows as of December 31, 2020 (in thousands): Operating Leases Finance Leases The remainder of fiscal 2021 $ 3,088 $ 9,241 2022 6,697 17,803 2023 5,561 12,904 2024 4,292 — 2025 3,617 — Thereafter 21,458 — Total minimum lease payments 44,713 39,948 Less amount representing interest (8,715) (2,592) Total lease liabilities $ 35,998 $ 37,356

Shareholders' Equity and Shar_2

Shareholders' Equity and Share-based Compensation (Tables)	6 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement, Noncash Expense [Abstract]
Restricted Stock Units Activity	Time-based Restricted Stock Units ("TRSU") The following table summarizes the Company's TRSU activities for the six months ended December 31, 2020: Number of Restricted Stock Weighted Average Weighted Average Aggregate Intrinsic Value Nonvested at June 30, 2020 932,138 $ 11.36 1.66 $ 10,141,661 Granted 211,635 $ 17.70 Vested (181,460) $ 16.27 Forfeited (13,375) $ 10.47 Nonvested at December 31, 2020 948,938 $ 11.85 1.29 $ 22,432,894 The following table summarizes the Company's PRSUs activities for the six months ended December 31, 2020: Number of Performance-based Restricted Stock Weighted Average Weighted Average Aggregate Intrinsic Value Nonvested at June 30, 2020 342,775 $ 12.38 1.60 $ 3,729,392 Forfeited (1,750) $ 16.61 Nonvested at December 31, 2020 341,025 $ 12.36 1.09 $ 8,061,831
Summary of Stock Option Activities	The following table summarizes the Company's stock option activities for the six months ended December 31, 2020: Weighted Weighted Average Average Remaining Number of Exercise Price Contractual Aggregate Shares Per Share Term (in years) Intrinsic Value Outstanding at June 30, 2020 643,978 $ 8.79 2.89 $ 1,544,664 Exercised (134,559) $ 11.60 Outstanding at December 31, 2020 509,419 $ 8.05 2.81 $ 7,940,606 Options vested and expected to vest 509,419 $ 8.05 2.81 $ 7,940,606 Exercisable at December 31, 2020 509,419 $ 8.05 2.81 $ 7,940,606
Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]	The assumptions used to estimate the fair values of common shares issued under the ESPP were as follows: Six Months Ended December 31, 2020 Volatility rate 63.1% Risk-free interest rate 0.2% Expected term 1.3 years Dividend yield 0%
Share-based Compensation, Allocation of Recognized Period Costs	Share-based Compensation Expense T he total share-based compensation expense recognized in the condensed consolidated statements of operations for the periods presented was as follows: Three Months Ended December 31, Six Months Ended December 31, 2020 2019 2020 2019 (in thousands) (in thousands) Cost of goods sold $ 383 $ 404 $ 768 $ 840 Research and development 1,243 472 2,323 996 Selling, general and administrative 1,598 1,611 3,009 3,020 $ 3,224 $ 2,487 $ 6,100 $ 4,856

Segment and Geographic Inform_2

Segment and Geographic Information (Tables)	6 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Disaggregation of Revenue [Table Text Block]	The Company sells its products primarily to distributors in the Asia Pacific region, who in turn sell these products to end customers. Because the Company's distributors sell their products to end customers which may have a global presence, revenue by geographical location is not necessarily representative of the geographical distribution of sales to end user markets. The revenue by geographical location in the following tables is based on the country or region in which the products were shipped to: Three Months Ended December 31, Six Months Ended December 31, 2020 2019 2020 2019 (in thousands) (in thousands) Hong Kong $ 134,506 $ 97,244 $ 261,106 $ 190,346 China 22,851 16,571 46,060 33,083 South Korea 146 2,279 282 8,269 United States 1,139 898 2,595 1,999 Other countries 188 868 338 1,965 $ 158,830 $ 117,860 $ 310,381 $ 235,662 The following is a summary of revenue by product type: Three Months Ended December 31, Six Months Ended December 31, 2020 2019 2020 2019 (in thousands) (in thousands) Power discrete $ 118,500 $ 99,321 * $ 232,872 $ 198,001 * Power IC 37,381 16,825 71,839 34,410 Packaging and testing services 2,949 1,714 5,670 3,251 $ 158,830 $ 117,860 $ 310,381 $ 235,662
Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas	Long-lived assets, net consisting of property, plant and equipment and land use rights, by geographical area are as follows: December 31, June 30, (in thousands) China $ 329,404 $ 310,600 United States 100,672 100,984 Other countries 732 756 $ 430,808 $ 412,340

The Company and Significant A_3

The Company and Significant Accounting Policies - Joint Venture (Details) - Facility in Liangjiang New Area of Chongqing (the 'Joint Venture')	Dec. 31, 2020
Simple Annual Interest Rate to Noncontrolling Interest if Joint Venture is Early Terminated and Liquidated	10.00%
Parent Company
Subsidiary or Equity Method Investee, Cumulative Percentage Ownership after All Transactions	51.00%
Chongqing Funds
Subsidiary or Equity Method Investee, Cumulative Percentage Ownership after All Transactions	49.00%

The Company and Significant A_4

The Company and Significant Accounting Policies - Restricted Cash (Details) - USD ($) $ in Millions	Dec. 31, 2020	Jun. 30, 2020
Accounting Policies [Abstract]
Restricted cash	$ 2.4	$ 4.2

The Company and Significant A_5

The Company and Significant Accounting Policies - Government Grants (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Government Grants, Reduction Recorded To Interest Expense	$ 0.7	$ 1.1	$ 1.5	$ 3.4
Government Grants, Reduction Recorded To Operating Expenses	1.7	0.5	3.6	0.5
Government Grants, Reduction Recorded To Property, Plant And Equipment	$ 0.1	$ 1.3	$ 0.1	$ 1.3

Net Income Per Common Share A_3

Net Income Per Common Share Attributable to Alpha and Omega Semiconductor Limited - Basic and Diluted Income Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Numerator:
Net income (loss) attributable to Alpha and Omega Semiconductor Limited	$ 12,903	$ (1,005)	$ 22,477	$ 4
Basic:
Weighted average number of common shares used to compute basic net income per share	25,672	24,701	25,506	24,620
Effect of potentially dilutive securities:
Stock options, RSUs and ESPP shares	1,681	0	1,328	742
Weighted average number of common shares used to compute diluted net income per share	27,353	24,701	26,834	25,362
Net income (loss) per share attributable to Alpha and Omega Semiconductor Limited:
Basic (in dollars per share)	$ 0.50	$ (0.04)	$ 0.88	$ 0
Diluted (in dollars per share)	$ 0.47	$ (0.04)	$ 0.84	$ 0

Net Income Per Common Share A_4

Net Income Per Common Share Attributable to Alpha and Omega Semiconductor Limited - Potential Dilutive Shares (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential dilutive securities (in shares)	42	2,908	200	934
Employee stock options and RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential dilutive securities (in shares)	7	2,040	66	337
ESPP
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential dilutive securities (in shares)	35	868	134	597

Concentration of Credit Risk _3

Concentration of Credit Risk and Significant Customers - (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2019	Jun. 30, 2019
Concentration Risk
Revenue			$ 158,830	$ 117,860	$ 310,381	$ 235,662
Minimum
Concentration Risk
Terms of credit sales, (in days)					30 days
Maximum
Concentration Risk
Terms of credit sales, (in days)					60 days
Huawei | Revenue | Customer Concentration Risk
Concentration Risk
Customers greater than 10% of total								2.00%
Huawei | Minimum | Revenue | Customer Concentration Risk
Concentration Risk
Revenue							$ 11,000
Huawei | Maximum | Revenue | Customer Concentration Risk
Concentration Risk
Revenue							$ 13,000
Customer A | Revenue | Customer Concentration Risk
Concentration Risk
Customers greater than 10% of total			28.40%	31.30%	28.60%	30.00%
Customer A | Accounts Receivable | Customer Concentration Risk
Concentration Risk
Customers greater than 10% of total	17.40%
Customer B | Revenue | Customer Concentration Risk
Concentration Risk
Customers greater than 10% of total			36.40%	37.00%	34.80%	36.00%
Customer B | Accounts Receivable | Customer Concentration Risk
Concentration Risk
Customers greater than 10% of total	14.40%
Customer C | Accounts Receivable | Customer Concentration Risk
Concentration Risk
Customers greater than 10% of total	23.60%	29.80%
Customer D | Accounts Receivable | Customer Concentration Risk
Concentration Risk
Customers greater than 10% of total	10.00%
Customer E | Accounts Receivable | Customer Concentration Risk
Concentration Risk
Customers greater than 10% of total		20.10%
Customer F | Accounts Receivable | Customer Concentration Risk
Concentration Risk
Customers greater than 10% of total		10.40%
Customer G | Accounts Receivable | Customer Concentration Risk
Concentration Risk
Customers greater than 10% of total		10.30%
Customer H | Accounts Receivable | Customer Concentration Risk
Concentration Risk
Customers greater than 10% of total		10.90%

Balance Sheet Components - Acco

Balance Sheet Components - Accounts receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 30, 2020
Balance Sheet Related Disclosures [Abstract]
Accounts receivable	$ 47,995	$ 43,394
Less: Allowance for price adjustments	(23,031)	(30,092)
Less: Allowance for doubtful accounts	(30)	(30)
Accounts receivable, net	$ 24,934	$ 13,272

Balance Sheet Components - Inve

Balance Sheet Components - Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 30, 2020
Balance Sheet Related Disclosures [Abstract]
Raw materials	$ 58,903	$ 55,377
Work in-process	65,680	61,863
Finished goods	19,724	18,288
Inventory, net	$ 144,307	$ 135,528

Balance Sheet Components - Othe

Balance Sheet Components - Other current assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 30, 2020
Balance Sheet Related Disclosures [Abstract]
VAT receivable	$ 2,194	$ 1,639
Other prepaid expenses	2,976	1,900
Prepaid insurance	1,956	1,520
Prepaid maintenance	746	587
Prepayment to supplier	990	938
Prepaid income tax	1,790	1,991
Customs deposit	0	163
Other receivables	181	69
Other Assets, Current	$ 10,833	$ 8,807

Balance Sheet Components - Prop

Balance Sheet Components - Property, plant, and equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 30, 2020
Property, Plant and Equipment [Line Items]
Property, plant, and equipment excluding equipment and construction In progress, gross	$ 715,398	$ 655,263
Land use rights	9,213	8,502
Less: accumulated depreciation	(324,344)	(291,515)
Property, plant and equipment excluding equipment and construction in progress, net	391,054	363,748
Equipment and construction in progress	39,754	48,592
Property, plant and equipment, net	430,808	412,340
Land
Property, Plant and Equipment [Line Items]
Property, plant, and equipment excluding equipment and construction In progress, gross	4,877	4,877
Building
Property, Plant and Equipment [Line Items]
Property, plant, and equipment excluding equipment and construction In progress, gross	63,696	58,875
Manufacturing machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant, and equipment excluding equipment and construction In progress, gross	493,487	447,079
Equipment and tooling
Property, Plant and Equipment [Line Items]
Property, plant, and equipment excluding equipment and construction In progress, gross	26,661	25,398
Computer equipment and software
Property, Plant and Equipment [Line Items]
Property, plant, and equipment excluding equipment and construction In progress, gross	40,004	38,779
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Property, plant, and equipment excluding equipment and construction In progress, gross	3,744	3,529
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant, and equipment excluding equipment and construction In progress, gross	$ 73,716	$ 68,224

Balance Sheet Components - Inta

Balance Sheet Components - Intangible assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 30, 2020
Schedule of Finite-lived Intangible Assets and Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross	$ 19,455	$ 19,455
Less: accumulated amortization	(4,634)	(2,954)
Finite-Lived Intangible Assets, Net	14,821	16,501
Goodwill	269	269
Intangible assets, net	15,090	16,770
Patents and technology rights
Schedule of Finite-lived Intangible Assets and Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross	18,037	18,037
Trade name
Schedule of Finite-lived Intangible Assets and Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross	268	268
Customer relationships
Schedule of Finite-lived Intangible Assets and Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross	$ 1,150	$ 1,150

Balance Sheet Components - Futu

Balance Sheet Components - Future Amortization of Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 30, 2020
Balance Sheet Related Disclosures [Abstract]
2021 (Remaining)	$ 1,680
2022	3,360
2023	3,286
2024	3,249
2025	3,246
Finite-Lived Intangible Assets, Net	$ 14,821	$ 16,501

Balance Sheet Components - Ot_2

Balance Sheet Components - Other long term assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 30, 2020
Balance Sheet Related Disclosures [Abstract]
Prepayments for property and equipment	$ 1,140	$ 2,242
Investment in a privately held company	100	100
Custom deposit, noncurrent	1,184	1,662
Other long-term deposits	916	850
Office lease deposit, noncurrent	1,103	766
Other	164	184
Other long-term assets	$ 4,607	$ 5,804

Balance Sheet Components - Accr

Balance Sheet Components - Accrued liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Balance Sheet Related Disclosures [Abstract]
Accrued compensation and benefits	$ 29,115	$ 19,968
Warranty accrual	767	709	$ 651	$ 623
Stock rotation accrual	3,893	3,358	$ 3,836	$ 1,921
Accrued professional fees	2,678	5,868
Accrued inventory	1,157	775
Accrued facilities related expenses	1,682	1,831
Accrued property, plant and equipment	9,924	11,039
Other accrued expenses	5,757	8,017
Customer deposit	4,663	2,813
ESPP payable	847	608
Accrued liabilities	$ 60,483	$ 54,986

Balance Sheet Components - Prod

Balance Sheet Components - Product Warranty Accrual (Details) - USD ($) $ in Thousands	6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Movement in Standard and Extended Product Warranty Accrual, Increase (Decrease) [Roll Forward]
Beginning balance	$ 709	$ 623
Additions	239	130
Utilization	(181)	(102)
Ending balance	$ 767	$ 651

Balance Sheet Components - Stoc

Balance Sheet Components - Stock Rotation Accrual (Details) - USD ($) $ in Thousands	6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Stock Rotation Accrual Increae (Decrease) [Roll Forward]
Beginning balance	$ 3,358	$ 1,921
Additions	4,180	5,990
Utilization	(3,645)	(4,075)
Ending balance	$ 3,893	$ 3,836

Balance Sheet Components - Ot_3

Balance Sheet Components - Other Long-Term Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 30, 2020
Balance Sheet Related Disclosures [Abstract]
Customer deposits	$ 15,000	$ 8,000
Computer software liabilities	960	1,897
Equipment liabilities	1,804	0
Deferred payroll taxes	2,432	826
Other long-term liabilities	$ 20,196	$ 10,723

Bank Borrowing (Details)

Bank Borrowing (Details)	Dec. 31, 2020USD ($)	Dec. 31, 2020CNY (¥)	Nov. 13, 2020USD ($)	Jun. 28, 2020	Jun. 24, 2020	Apr. 26, 2020USD ($)	Aug. 09, 2019USD ($)	Mar. 12, 2019USD ($)	May 09, 2018USD ($)	May 01, 2018USD ($)	Aug. 15, 2017USD ($)	Apr. 30, 2020USD ($)	Apr. 30, 2020CNY (¥)	Dec. 31, 2019CNY (¥)	Oct. 31, 2019USD ($)	Mar. 31, 2019CNY (¥)	Jul. 31, 2018USD ($)	Jan. 31, 2018USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2020CNY (¥)	Jun. 30, 2020USD ($)	Jun. 30, 2020CNY (¥)	Dec. 31, 2020USD ($)	Dec. 31, 2020CNY (¥)	Nov. 13, 2020CNY (¥)	Apr. 26, 2020CNY (¥)	Apr. 15, 2020USD ($)	Apr. 15, 2020CNY (¥)	Dec. 31, 2019USD ($)	Oct. 31, 2019CNY (¥)	Mar. 12, 2019CNY (¥)	Dec. 31, 2018USD ($)	Dec. 04, 2018CNY (¥)	Nov. 29, 2018CNY (¥)	Nov. 16, 2018USD ($)	Nov. 16, 2018CNY (¥)	May 09, 2018CNY (¥)
Debt Instrument [Line Items]
Restricted cash	$ 2,400,000																		$ 2,400,000		$ 4,200,000		$ 2,400,000
Maturities of debt
2021 (Remaining)	24,784,000																		24,784,000				24,784,000
2022	35,127,000																		35,127,000				35,127,000
2023	38,256,000																		38,256,000				38,256,000
2024	24,125,000																		24,125,000				24,125,000
2025	15,566,000																		15,566,000				15,566,000
Total principal	137,858,000																		137,858,000				137,858,000
Less: debt issuance costs	(1,188,000)																		(1,188,000)				(1,188,000)
Total principal, less debt issuance costs	136,670,000																		136,670,000				136,670,000
Long-term Debt, Current Maturities	43,574,000																		43,574,000		30,114,000		43,574,000
Long-term Debt, Excluding Current Maturities	93,096,000																		93,096,000		99,775,000		93,096,000
Long-term Debt, Current Maturities, And Short-Term Debt, Gross	44,060,000																		44,060,000				44,060,000
Long-term Debt, Excluding Current Maturities, Gross	93,798,000																		93,798,000				93,798,000
Debt Issuance Costs, Gross, Current	(486,000)																		(486,000)				(486,000)
Debt Issuance Cost, Gross, Noncurrent	(702,000)																		(702,000)				(702,000)
Long-term Debt, Current Maturities, And Short-term Debt	43,574,000																		43,574,000				43,574,000
Bank Of Communications Limited
Debt Instrument [Line Items]
Loan agreements, short-term debt	0																		0				0
Line of credit facility, maximum borrowing capacity															$ 8,500,000															¥ 60,000,000
China Merchant Bank And Chongqing LiangJiang New District China Merchants Group Limited Company | Loan Agreement November 29 2018
Debt Instrument [Line Items]
Debt instrument, face amount | ¥																																		¥ 80,000,000
China Merchant Bank And Chongqing LiangJiang New District China Merchants Group Limited Company | Loan Agreement December 4 2018
Debt Instrument [Line Items]
Debt instrument, face amount | ¥																																	¥ 20,000,000
China Merchant Bank And Chongqing LiangJiang New District China Merchants Group Limited Company | Loan Agreements November 29 And December 4 2018
Debt Instrument [Line Items]
Debt instrument, face amount																																$ 14,500,000
Loan agreements, short-term debt	0																		0				0
Hongkong And Shanghai Banking Corporation Limited | Secured Debt | Accounts Receivable Factoring Agreement August 9 2019
Debt Instrument [Line Items]
Basis spread on variable rate							1.75%
Accounts receivable factoring agreement, maximum borrowing capacity, percent of net accounts receivable							70.00%
Accounts receivable factoring agreement, maximum borrowing capacity							$ 30,000,000
Accounts receivable factoring agreement, remaining borrowing capacity	30,000,000																		30,000,000				30,000,000
Proceeds from accounts receivable factoring agreement																			7,000,000				36,700,000
Repayments of accounts receivable factoring agreement																			7,000,000				36,700,000
Accounts receivable factoring agreement, borrowed amount outstanding	0																		0				0
YinHai Leasing Company and China Import/Export Bank | Lease Financing
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity									$ 62,800,000																												¥ 400,000,000
Debt instrument, term									5 years
Nominal sale amount at end of lease term | ¥																																					¥ 1
Amount outstanding	37,400,000																		37,400,000				37,400,000	¥ 244,000,000
YinHai Leasing Company and China Import/Export Bank | China Five-Year Loan Prime Rate | Lease Financing
Debt Instrument [Line Items]
Basis spread on variable rate				0.8125%
Debt Instrument effective interest rate				5.4625%
China Development Bank | Secured Debt
Debt Instrument [Line Items]
Debt instrument, face amount																													$ 24,000,000
Long-term debt	21,600,000																		21,600,000				21,600,000
China Development Bank | London Interbank Offered Rate (LIBOR) | Secured Debt
Debt Instrument [Line Items]
Basis spread on variable rate														2.80%
Export-Import Bank Of China
Debt Instrument [Line Items]
Restricted cash								$ 2,000,000																							¥ 14,000,000
Line of credit facility outstanding balance	28,900,000	¥ 189,000,000
Export-Import Bank Of China | Secured Debt
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity								$ 29,800,000																							¥ 200,000,000
Proceeds from lines of credit | ¥														¥ 10,000,000		¥ 190,000,000
Maturities of debt
Line Of Credit Facility, Interest Rate During Period, China Base Rate Multiplier								1.1
Line of Credit Facility, Interest Rate During Period					5.39%			5.39%
Export-Import Bank Of China | China Five-Year Loan Prime Rate | Secured Debt
Debt Instrument [Line Items]
Basis spread on variable rate					0.74%
China Development Bank, Agricultural Bank of China, China Merchant Bank and Chongqing Rural Commercial Bank [Member] | Secured Debt
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity						$ 35,700,000																				¥ 250,000,000
Amount outstanding	36,000,000																		36,000,000				36,000,000
Proceeds from lines of credit												$ 35,300,000	¥ 250,000,000
China Development Bank, Agricultural Bank of China, China Merchant Bank and Chongqing Rural Commercial Bank [Member] | China One-Year Loan Prime Rate | Secured Debt
Debt Instrument [Line Items]
Basis spread on variable rate						1.30%
The Bank | Secured Debt
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity										$ 17,800,000
Debt instrument, term										5 years
Amount outstanding	15,500,000																		15,500,000				15,500,000
Stated percentage										5.04%
The Bank | Term Loan | Secured Debt | Variable Interest Rate Term Loan Maturing August 2022
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity											$ 30,000,000
Debt instrument, term											5 years
Amount outstanding	13,000,000																		13,000,000				13,000,000
Proceeds from lines of credit																	$ 16,700,000	$ 13,200,000
The Bank | Minimum | London Interbank Offered Rate (LIBOR) | Term Loan | Secured Debt | Variable Interest Rate Term Loan Maturing August 2022
Debt Instrument [Line Items]
Basis spread on variable rate											1.75%
The Bank | Maximum | London Interbank Offered Rate (LIBOR) | Term Loan | Secured Debt | Variable Interest Rate Term Loan Maturing August 2022
Debt Instrument [Line Items]
Basis spread on variable rate											2.25%
China | Bank Of Communications Limited | Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate															4.99%
Basis spread on variable rate, multiple															1.05															1.05
China | YinHai Leasing Company and China Import/Export Bank | Base Rate | Lease Financing
Debt Instrument [Line Items]
Basis spread on variable rate									5.4625%
Basis spread on variable rate, multiple									1.15																												1.15
Foreign Line of Credit | Industrial And Commercial Bank of China
Debt Instrument [Line Items]
Loan agreements, short-term debt	$ 0																		0				$ 0
Line of credit facility, maximum borrowing capacity																																			$ 10,300,000	¥ 72,000,000
Loans Payable | Loan Agreement, November 13, 2020
Debt Instrument [Line Items]
Debt instrument, face amount			$ 7,600,000																						¥ 50,000,000
Proceeds from short-term debt																			$ 7,700,000	¥ 50,000,000
Short-term debt, fixed interest rate	5.25%																		5.25%				5.25%	5.25%
Loan agreements, short-term debt	$ 7,700,000																		$ 7,700,000				$ 7,700,000
Loans Payable | Loan Agreement April 15, 2020
Debt Instrument [Line Items]
Debt instrument, face amount																											$ 14,300,000	¥ 100,000,000
Proceeds from short-term debt																			$ 12,100,000		$ 3,100,000	¥ 20,000,000
Short-term debt, fixed interest rate	2.70%																		2.70%				2.70%	2.70%
Loan agreements, short-term debt	$ 15,200,000																		$ 15,200,000				$ 15,200,000
Loans Payable | Loan Agreement, April 15, 2020, Working Capital Borrowing In Chinese Yuan
Debt Instrument [Line Items]
Debt instrument, face amount | ¥																												20,000,000
Loans Payable | Loan Agreement, April 15, 2020, Collateralized Borrowings In US Dollars
Debt Instrument [Line Items]
Debt instrument, face amount | ¥																												¥ 80,000,000
Loans Payable | China One-Year Loan Prime Rate | Loan Agreement, November 13, 2020
Debt Instrument [Line Items]
Basis spread on variable rate			1.40%

Leases - Narrative (Details)

Leases - Narrative (Details) $ in Thousands, ¥ in Millions	Dec. 31, 2020USD ($)	Jun. 30, 2020USD ($)	May 09, 2018USD ($)	May 09, 2018CNY (¥)
Debt Instrument [Line Items]
Operating lease liability	$ 35,998
ROU assets associated with operating leases	$ 34,395	$ 32,948
Lease Financing | YinHai Leasing Company and China Import/Export Bank
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			$ 62,800	¥ 400

Leases - Schedule of Operating

Leases - Schedule of Operating and Finance Lease Expenses (Details) - USD ($) $ in Thousands	6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating Leases:
Fixed rent expense	$ 3,407	$ 2,614
Variable rent expense	419	421
Finance Lease:
Amortization of equipment	1,149	1,716
Interest	1,187	1,457
Short-term leases
Short-term lease expenses	107	152
Total lease expenses	$ 6,269	$ 6,360

Leases - Supplemental Balance S

Leases - Supplemental Balance Sheet Information (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 30, 2020
Operating Leases:
ROU assets associated with operating leases	$ 34,395	$ 32,948
Finance Lease:
Property, plant and equipment, gross	113,108	104,374
Accumulated depreciation	(94,607)	(86,540)
Property, plant and equipment, net	$ 18,501	$ 17,834
Weighted average remaining lease term (in years)
Operating leases	8 years 10 months 13 days	9 years 6 months 25 days
Finance lease	2 years 2 months 19 days	2 years 8 months 19 days
Weighted average discount rate
Operating leases	4.50%	4.45%
Finance lease	5.46%	5.46%

Leases - Supplemental Cash Flow

Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Cash paid from amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 3,341	$ 2,541
Operating cash flows from finance lease	1,187	1,457
Financing cash flows from finance lease	8,119	3,403
Operating lease right-of-use assets obtained in exchange for lease obligations	$ 2,824	$ 16,088

Leases - Future Minimum Lease P

Leases - Future Minimum Lease Payments (Topic 842) (Details) $ in Thousands	Dec. 31, 2020USD ($)
Operating Leases
The remainder of fiscal 2021	$ 3,088
2022	6,697
2023	5,561
2024	4,292
2025	3,617
Thereafter	21,458
Total minimum lease payments	44,713
Less amount representing interest	(8,715)
Total lease liabilities	35,998
Finance Leases
The remainder of fiscal 2021	9,241
2022	17,803
2023	12,904
2024	0
2025	0
Thereafter	0
Total minimum lease payments	39,948
Less amount representing interest	(2,592)
Total lease liabilities	$ 37,356

Shareholders' Equity and Shar_3

Shareholders' Equity and Share-based Compensation - Shares Repurchase (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended		119 Months Ended	122 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2020	Dec. 31, 2020
Class of Stock [Line Items]
Treasury Stock, Shares, Retired						0
Share repurchase program, authorized amount (USD in Millions)	$ 30,000		$ 30,000			$ 30,000
Repurchase of common shares under shares repurchase program			0		6,784,648	6,784,648
Treasury stock acquired, average price per share (in dollars per share)						$ 9.92
Repurchase of common shares under shares repurchase program						$ (67,300)
Shares repurchase program, remaining balance	$ 13,400		$ 13,400			$ 13,400
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	0	0	0	0
Share-based payment arrangement, expense	$ 3,224	$ 2,487	$ 6,100	$ 4,856
Treasury Stock Reissued
Class of Stock [Line Items]
Treasury stock acquired, average price per share (in dollars per share)						$ 10.19
Shares reissued (in shares)					155,670
Shares reissued, average price (in dollars per share)						$ 5.37
Market-based Restricted Stock Units (MSU) [Member]
Class of Stock [Line Items]
Share-based payment arrangement, expense	$ 400	$ 100	$ 600	$ 300

Shareholders' Equity and Shar_4

Shareholders' Equity and Share-based Compensation - Time-based Restricted Stock Activity (Details) - USD ($)	6 Months Ended	12 Months Ended
	Dec. 31, 2020	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Weighted average remaining recognition period (in years)	2 years 4 months 24 days
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Nonvested at beginning of period (in shares)	932,138
Granted (in shares)	211,635
Vested (in shares)	(181,460)
Forfeited (in shares)	(13,375)
Nonvested at end of period (in shares)	948,938	932,138
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Nonvested at beginning of period (in dollars per share)	$ 11.36
Granted (in dollars per share)	17.70
Vested (in dollars per share)	16.27
Forfeited (in dollars per share)	10.47
Nonvested at end of period (in dollars per share	$ 11.85	$ 11.36
Weighted average remaining recognition period (in years)	1 year 3 months 14 days	1 year 7 months 28 days
Aggregate Intrinsic Value	$ 22,432,894	$ 10,141,661

Shareholders' Equity and Shar_5

Shareholders' Equity and Share-based Compensation - Market-based Restricted Stock Units Narrative (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2018	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	$ 3,224	$ 2,487		$ 6,100	$ 4,856
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Weighted average remaining recognition period (in years)				2 years 4 months 24 days
Market-based Restricted Stock Units (MSU) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	$ 400	$ 100		$ 600	$ 300
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Granted (in shares)			1,300,000

Shareholders' Equity and Shar_6

Shareholders' Equity and Share-based Compensation - Performance-based Restricted Stock Units (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	$ 3,224,000	$ 2,487,000	$ 6,100,000	$ 4,856,000
Share-based payment arrangement, expense, non-cash	600,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Weighted average remaining recognition period (in years)			2 years 4 months 24 days
Performance Based Restricted Stock Units (PRSUs) Member
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	400,000	$ 500,000	$ 800,000	$ 700,000
Value of grants in period	$ 1,000,000		$ 2,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Nonvested at beginning of period (in shares)			342,775
Forfeited (in shares)			(1,750)
Nonvested at end of period (in shares)	341,025		341,025		342,775
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Nonvested at beginning of period (in dollars per share)			$ 12.38
Forfeited (in dollars per share)			16.61
Nonvested at end of period (in dollars per share	$ 12.36		$ 12.36		$ 12.38
Weighted average remaining recognition period (in years)			1 year 1 month 2 days		1 year 7 months 6 days
Aggregate Intrinsic Value	$ 8,061,831		$ 8,061,831		$ 3,729,392

Shareholders' Equity and Shar_7

Shareholders' Equity and Share-based Compensation - Stock Options Outstanding and Exercisable (Details) - USD ($)	6 Months Ended	12 Months Ended
	Dec. 31, 2020	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding at beginning of period (in shares)	643,978
Exercised (in shares)	(134,559)
Outstanding at end of period (In shares)	509,419	643,978
Options vested and expected to vest (in shares)	509,419
Exercisable at end of period (in shares)	509,419
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding at beginning of period (in dollars per share)	$ 8.79
Exercised (in dollars per share)	11.60
Outstanding at end of period (in dollars per share)	8.05	$ 8.79
Options vested and expected to vest (in dollars per share)	8.05
Exercisable at end of period (in dollars per share)	$ 8.05
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Options outstanding, Weighted-Average Remaining Contractual Life (in years)	2 years 9 months 21 days	2 years 10 months 20 days
Options vested and expected to vest, Weighted Average Remaining Contractual Life (in years)	2 years 9 months 21 days
Exercisable at end of period, Weighted Average Remaining Contractual Life (in years)	2 years 9 months 21 days
Options outstanding, Aggregate Intrinsic Value	$ 7,940,606	$ 1,544,664
Options vested and expected to vest, Aggregate Intrinsic Value	7,940,606
Exercisable at end of period, Aggregate Intrinsic Value	$ 7,940,606

Shareholders' Equity and Shar_8

Shareholders' Equity and Share-based Compensation - Employee Share Purchase Plan (Details) - shares	6 Months Ended	119 Months Ended	122 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Repurchase of common shares under shares repurchase program	0	6,784,648	6,784,648
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility rate	63.10%
Risk-free interest rate	0.20%
Expected term	1 year 3 months 18 days
Dividend yield	0.00%

Shareholders' Equity and Shar_9

Shareholders' Equity and Share-based Compensation - Share-based Compensation (Details) - USD ($)	3 Months Ended			6 Months Ended		12 Months Ended	119 Months Ended	122 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Jun. 30, 2020	Sep. 30, 2020	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	$ 3,224,000	$ 2,487,000		$ 6,100,000	$ 4,856,000
Repurchase of common shares under shares repurchase program				0			6,784,648	6,784,648
Options outstanding, Weighted-Average Remaining Contractual Life (in years)				2 years 9 months 21 days		2 years 10 months 20 days
Options vested and expected to vest (in shares)	509,419			509,419				509,419
Options vested and expected to vest (in dollars per share)	$ 8.05			$ 8.05				$ 8.05
Options vested and expected to vest, Weighted Average Remaining Contractual Life (in years)				2 years 9 months 21 days
Options vested and expected to vest, Aggregate Intrinsic Value	$ 7,940,606			$ 7,940,606				$ 7,940,606
Exercisable at end of period (in shares)	509,419			509,419				509,419
Exercisable at end of period (in dollars per share)	$ 8.05			$ 8.05				$ 8.05
Exercisable at end of period, Weighted Average Remaining Contractual Life (in years)				2 years 9 months 21 days
Exercisable at end of period, Aggregate Intrinsic Value	$ 7,940,606			$ 7,940,606				$ 7,940,606
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding at beginning of period (in shares)				643,978
Outstanding at end of period (In shares)	509,419			509,419		643,978		509,419
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding at beginning of period (in dollars per share)				$ 8.79
Outstanding at end of period (in dollars per share)	$ 8.05			$ 8.05		$ 8.79		$ 8.05
Options outstanding, Aggregate Intrinsic Value	$ 7,940,606			$ 7,940,606		$ 1,544,664		$ 7,940,606
Market-based Restricted Stock Units (MSU) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	400,000	100,000		600,000	300,000
Granted (in shares)			1,300,000
Performance Based Restricted Stock Units (PRSUs) Member
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	$ 400,000	$ 500,000		$ 800,000	$ 700,000

Shareholders' Equity and Sha_10

Shareholders' Equity and Share-based Compensation - Share-based Compensation Expenses (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based payment arrangement, expense	$ 3,224	$ 2,487	$ 6,100	$ 4,856
Unrecognized compensation expense	12,400		$ 12,400
Recognition period of share-based compensation expense (in years)			2 years 4 months 24 days
Cost of goods sold
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based payment arrangement, expense	383	404	$ 768	840
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based payment arrangement, expense	1,243	472	2,323	996
Selling, general and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based payment arrangement, expense	$ 1,598	$ 1,611	$ 3,009	$ 3,020

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($)	3 Months Ended			6 Months Ended		65 Months Ended
	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020
Income Tax Contingency [Line Items]
Income tax expense	$ 669,000		$ 568,000	$ 1,680,000	$ 978,000
Discrete income tax expense (benefit)	$ (10,000)	$ 1,100,000	$ 10,000	$ (20,000)	$ (30,000)
Estimated effective income tax rate excluding discrete income tax expense	5.00%		(13.80%)	7.40%	(17.40%)
Income (loss) before income taxes	$ 13,209,000		$ (4,005,000)	$ 22,987,000	$ (5,453,000)
Unrecognized tax benefits	7,200,000			7,200,000		$ 7,200,000
Unrecognized tax benefit that would impact effective tax rate	$ 4,300,000			$ 4,300,000		4,300,000
Altera Corp. V. Commissioner
Income Tax Contingency [Line Items]
Benefit related to Altera Corporation Tax Court decision						$ 0

Segment and Geographic Inform_3

Segment and Geographic Information - Revenue by Location and Product Type (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 158,830	$ 117,860	$ 310,381	$ 235,662
Power discrete
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	118,500	99,321	232,872	198,001
Power IC
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	37,381	16,825	71,839	34,410
Packaging and testing services
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	2,949	1,714	5,670	3,251
Hong Kong
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	134,506	97,244	261,106	190,346
China
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	22,851	16,571	46,060	33,083
South Korea
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	146	2,279	282	8,269
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	1,139	898	2,595	1,999
Other countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 188	$ 868	$ 338	$ 1,965

Segment and Geographic Inform_4

Segment and Geographic Information - Long-lived Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 30, 2020
Revenues from External Customers and Long-Lived Assets [Line Items]
Property, plant and equipment, net and land use rights, net	$ 430,808	$ 412,340
China
Revenues from External Customers and Long-Lived Assets [Line Items]
Property, plant and equipment, net and land use rights, net	329,404	310,600
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Property, plant and equipment, net and land use rights, net	100,672	100,984
Other countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Property, plant and equipment, net and land use rights, net	$ 732	$ 756

Segment and Geographic Inform_5

Segment and Geographic Information - Narratives (Details)	6 Months Ended
	Dec. 31, 2020Segment
Segment Reporting [Abstract]
Number of operating segments	1
Number of reportable segments	1

Commitments and Contingencies -

Commitments and Contingencies - Purchase Commitments (Details) - USD ($) $ in Millions	Dec. 31, 2020	Jun. 30, 2020
Raw materials, wafers, and packaging and testing services puchase commitments
Purchase Commitment, Excluding Long-term Committment [Line Items]
Purchase commitment, amount	$ 45.6	$ 43.9
Property and equipment purchase commitments
Purchase Commitment, Excluding Long-term Committment [Line Items]
Purchase commitment, amount	$ 38.1	$ 18

Commitments and Contingencies_2

Commitments and Contingencies - Contingencies and Indemnities (Details) - USD ($)	Dec. 31, 2020	Jun. 30, 2020
Indemnification Agreement
Loss Contingencies [Line Items]
Indemnifications accrual	$ 0	$ 0