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  <xsd:element name="DonghaiCountyDongfangHighPurityElectronicMaterialsCoLtdMember" id="axti_DonghaiCountyDongfangHighPurityElectronicMaterialsCoLtdMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="BeijingTongmeiXtalTechnologyMember" id="axti_BeijingTongmeiXtalTechnologyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element id="axti_NanjingJinMeiGalliumCoLtdMember" name="NanjingJinMeiGalliumCoLtdMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_InvestmentsInJointVenturesConsolidated" name="InvestmentsInJointVenturesConsolidated" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element name="ShareBasedCompensationNonvestedAwardsEstimatedForfeitures" id="axti_ShareBasedCompensationNonvestedAwardsEstimatedForfeitures" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="WeightedAverageRemainingContractualLifeAbstract" id="axti_WeightedAverageRemainingContractualLifeAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AsiaPacificExcludingJapanAndTaiwanMember" id="axti_AsiaPacificExcludingJapanAndTaiwanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element id="axti_BeijingBoyuSemiconductorVesselCraftworkTechnologyCoMember" name="BeijingBoyuSemiconductorVesselCraftworkTechnologyCoMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_MinorityInvestmentEntitiesNotConsolidatedAccountedForByEquityMethod" name="MinorityInvestmentEntitiesNotConsolidatedAccountedForByEquityMethod" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element name="ExcessAndObsoleteInventory" id="axti_ExcessAndObsoleteInventory" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element name="LoanToRelatedPartyMember" id="axti_LoanToRelatedPartyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="RawMaterialsPurchasesFromRelatedPartyMember" id="axti_RawMaterialsPurchasesFromRelatedPartyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AccountsPayableBalanceSheetLocationMember" id="axti_AccountsPayableBalanceSheetLocationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element id="axti_BeijingJiyaSemiconductorMaterialCo.LtdInvestmentMember" name="BeijingJiyaSemiconductorMaterialCo.LtdInvestmentMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_NanjingJinMeiGalliumCo.LtdInvestmentMember" name="NanjingJinMeiGalliumCo.LtdInvestmentMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_BeijingBoyuSemiconductorVesselCraftworkTechnologyCo.LtdInvestmentMember" name="BeijingBoyuSemiconductorVesselCraftworkTechnologyCo.LtdInvestmentMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_DonghaiCountyDongfangHighPurityElectronicMaterialsCo.LtdInvestmentMember" name="DonghaiCountyDongfangHighPurityElectronicMaterialsCo.LtdInvestmentMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_EmeishanJiaMeiHighPurityMetalsCo.LtdInvestmentMember" name="EmeishanJiaMeiHighPurityMetalsCo.LtdInvestmentMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element name="SubstratesMember" id="axti_SubstratesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="RawMaterialsAndOthersMember" id="axti_RawMaterialsAndOthersMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element id="axti_PreferredStockDividendsPayable" name="PreferredStockDividendsPayable" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="axti_AccountingForSalesTaxesInNetRevenuesPolicyTextBlock" name="AccountingForSalesTaxesInNetRevenuesPolicyTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element name="ImpairedInvestmentPolicyPolicyTextBlock" id="axti_ImpairedInvestmentPolicyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EquityMethodInvestmentSummarizedIncomeInformationTableTextBlock" id="axti_EquityMethodInvestmentSummarizedIncomeInformationTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EquityMethodInvestmentSummarizedBalanceSheetInformationTableTextBlock" id="axti_EquityMethodInvestmentSummarizedBalanceSheetInformationTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ScheduleOfShareBasedCompensationCommonStockReservedForFutureIssuanceTableTextBlock" id="axti_ScheduleOfShareBasedCompensationCommonStockReservedForFutureIssuanceTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element id="axti_SpecialtyMaterialSubstratesMember" name="SpecialtyMaterialSubstratesMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_RawMaterialsMember" name="RawMaterialsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element name="NumberOfProductLines" id="axti_NumberOfProductLines" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="TemperatureInCelsius" id="axti_TemperatureInCelsius" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="StockOptionPlanMember" id="axti_StockOptionPlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EquityIncentivePlanMember" id="axti_EquityIncentivePlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element id="axti_EquityIncentive2015PlanMember" name="EquityIncentive2015PlanMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_TimeBasedVestingMember" name="TimeBasedVestingMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_PerformanceBasedVestingMember" name="PerformanceBasedVestingMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_ConsultantMember" name="ConsultantMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_PriceRangeOneMember" name="PriceRangeOneMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_PriceRangeTwoMember" name="PriceRangeTwoMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_PriceRangeFourMember" name="PriceRangeFourMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_PriceRangeFiveMember" name="PriceRangeFiveMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_PriceRangeSixMember" name="PriceRangeSixMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_PriceRangeSevenMember" name="PriceRangeSevenMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_PriceRangeEightMember" name="PriceRangeEightMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_PriceRangeNineMember" name="PriceRangeNineMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_PriceRangeTenMember" name="PriceRangeTenMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element name="PeriodAfterWhichAllFullTimeEmployeesAreEligibleToParticipateInSavingsPlan" id="axti_PeriodAfterWhichAllFullTimeEmployeesAreEligibleToParticipateInSavingsPlan" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationForeignIncomeTaxIncentive" id="axti_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxIncentive" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EnterpriseIncomeTaxLawPercentage" id="axti_EnterpriseIncomeTaxLawPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PreferentialTaxRate" id="axti_PreferentialTaxRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <xsd:element id="axti_OtherNonoperatingIncomeExpenseOthers" name="OtherNonoperatingIncomeExpenseOthers" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="axti_ConstructionInProgressManufacturingEquipmentPurchasesMember" name="ConstructionInProgressManufacturingEquipmentPurchasesMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_ConstructionInProgressOtherConsolidatedSubsidiariesMember" name="ConstructionInProgressOtherConsolidatedSubsidiariesMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_TotalInvestmentAgreementValue" name="TotalInvestmentAgreementValue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="axti_DingxingMember" name="DingxingMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_KazuoMember" name="KazuoMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_EffectOfStockBasedCompensationOnDilutedEarningsPerShare" name="EffectOfStockBasedCompensationOnDilutedEarningsPerShare" nillable="true" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="axti_EffectOfStockBasedCompensationOnBasicEarningsPerShare" name="EffectOfStockBasedCompensationOnBasicEarningsPerShare" nillable="true" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="axti_BeijingBoyuSemiconductorVesselCraftworkTechnologyCoLtdMember" name="BeijingBoyuSemiconductorVesselCraftworkTechnologyCoLtdMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_OtherPersonnelRelatedCostsCurrent" name="OtherPersonnelRelatedCostsCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="axti_BenefitFromPreferentialTaxRatePercentage" name="BenefitFromPreferentialTaxRatePercentage" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="axti_AccumulatedOtherComprehensiveIncomeCumulativeTranslationAdjustmentAttributableToNoncontrollingInterests" name="AccumulatedOtherComprehensiveIncomeCumulativeTranslationAdjustmentAttributableToNoncontrollingInterests" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="axti_EquityMethodInvestmentsIncomeLossExcludingImpairmentCharges" name="EquityMethodInvestmentsIncomeLossExcludingImpairmentCharges" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="axti_ContractWithCustomerLiabilityTableTextBlock" name="ContractWithCustomerLiabilityTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="axti_CashAndCashEquivalentsAndDebtSecuritiesAvailableForSaleAmortizedCost" name="CashAndCashEquivalentsAndDebtSecuritiesAvailableForSaleAmortizedCost" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="axti_CashAndCashEquivalentsAndDebtSecuritiesAvailableForSale" name="CashAndCashEquivalentsAndDebtSecuritiesAvailableForSale" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="axti_ExpectedPeriodToReceiveSalesCommissions" name="ExpectedPeriodToReceiveSalesCommissions" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="axti_IndustrialAndCommercialBankOfChinaMember" name="IndustrialAndCommercialBankOfChinaMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_AllowanceForSalesReturnMember" name="AllowanceForSalesReturnMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_BalanceSheetDetailDisclosureAbstract" name="BalanceSheetDetailDisclosureAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_BalanceSheetDetailDisclosureTextBlock" name="BalanceSheetDetailDisclosureTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="axti_CurrentPayableInConnectionWithConstructions" name="CurrentPayableInConnectionWithConstructions" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="axti_ValuationAllowancesAndReservesAdditionalDeduction" name="ValuationAllowancesAndReservesAdditionalDeduction" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="axti_FiveMinorityInvestmentsMember" name="FiveMinorityInvestmentsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_LesseeWeightedAverageRemainingLeaseTermAndWeightedAverageDiscountRateOfLeasesTableTextBlock" name="LesseeWeightedAverageRemainingLeaseTermAndWeightedAverageDiscountRateOfLeasesTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="axti_LesseeSupplementalCashFlowInformationOfLeasesTableTextBlock" name="LesseeSupplementalCashFlowInformationOfLeasesTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="axti_XiaoyiXinganGalliumCo.Ltd.Member" name="XiaoyiXinganGalliumCo.Ltd.Member" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_InvestmentsTableTextBlock" name="InvestmentsTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="axti_InvestmentScheduleAbstract" name="InvestmentScheduleAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_DeferredTaxAssetsOperatingLeaseLiability" name="DeferredTaxAssetsOperatingLeaseLiability" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="axti_TermOfAgreement" name="TermOfAgreement" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="axti_CrossLicenseAgreementMember" name="CrossLicenseAgreementMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_LinesOfCreditCurrentMember" name="LinesOfCreditCurrentMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_BankOfChinaMember" name="BankOfChinaMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_ChaoyangJinmeiGalliumCo.LtdMember" name="ChaoyangJinmeiGalliumCo.LtdMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_RedeemableNonControllingInterestsStockIssuanceCosts" name="RedeemableNonControllingInterestsStockIssuanceCosts" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="axti_ProceedsFromIssuanceOfCommonStockToRedeemableNonControllingInterests" name="ProceedsFromIssuanceOfCommonStockToRedeemableNonControllingInterests" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="axti_InvestmentsApprovedByGovernment" name="InvestmentsApprovedByGovernment" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="axti_PercentageOfEquityIssuedOnConversionOfNonControllingInterests" name="PercentageOfEquityIssuedOnConversionOfNonControllingInterests" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="axti_PercentageOfEquityPurchasedByEmployeesKeyManagersAndContributors" name="PercentageOfEquityPurchasedByEmployeesKeyManagersAndContributors" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="axti_ConstructionInProgressDingxinAndKazuoLocationsMember" name="ConstructionInProgressDingxinAndKazuoLocationsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_RedeemableNonControllingInterestsOwnershipPercentage" name="RedeemableNonControllingInterestsOwnershipPercentage" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="axti_ChaoyangXinmeiHighPuritySemiconductorMaterialsCo.LtdMember" name="ChaoyangXinmeiHighPuritySemiconductorMaterialsCo.LtdMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_TotalInvestmentOfJointVentureAgreement" name="TotalInvestmentOfJointVentureAgreement" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="axti_JointVentureAgreementInitialInvestmentFundsCollected" name="JointVentureAgreementInitialInvestmentFundsCollected" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="axti_PercentageOfTargetedFinancialPerformance" name="PercentageOfTargetedFinancialPerformance" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="axti_NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsOtherNonredeemable" name="NoncontrollingInterestInNetIncomeLossOtherNoncontrollingInterestsOtherNonredeemable" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="axti_TransferOfSubsidiaryWithRedeemableNoncontrollingInterest" name="TransferOfSubsidiaryWithRedeemableNoncontrollingInterest" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="axti_AxtTongmeiInc.Member" name="AxtTongmeiInc.Member" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_IncreaseInNoncontrollingInterestsDueToTransferOfSubsidiaryWithNoncontrollingInterests" name="IncreaseInNoncontrollingInterestsDueToTransferOfSubsidiaryWithNoncontrollingInterests" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="axti_IncreaseInRedeemableNoncontrollingInterestsDueToTransferOfSubsidiaryWithNoncontrollingInterests" name="IncreaseInRedeemableNoncontrollingInterestsDueToTransferOfSubsidiaryWithNoncontrollingInterests" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="axti_EquityMethodInvestmentReturnsOrDividends" name="EquityMethodInvestmentReturnsOrDividends" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="axti_MinorityInvestorMember" name="MinorityInvestorMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_LoanFromRelatedPartyMember" name="LoanFromRelatedPartyMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="axti_ProceedsFromSaleOfSubsidiarySharesToNoncontrollingInterestsNet" name="ProceedsFromSaleOfSubsidiarySharesToNoncontrollingInterestsNet" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element name="IncomeLossFromGovernmentSubsidy" id="axti_IncomeLossFromGovernmentSubsidy" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationGainLossFromSaleOfIntellectualPropertyPercent" id="axti_EffectiveIncomeTaxRateReconciliationGainLossFromSaleOfIntellectualPropertyPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="BankOfCommunicationsMember" id="axti_BankOfCommunicationsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ChinaMerchantsBankMember" id="axti_ChinaMerchantsBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TransferOfSubsidiaryWithNoncontrollingInterests" id="axti_TransferOfSubsidiaryWithNoncontrollingInterests" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="StockBasedCompensationAttributableToNoncontrollingInterest" id="axti_StockBasedCompensationAttributableToNoncontrollingInterest" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DebtInstrumentGuaranteeFeePercentage" id="axti_DebtInstrumentGuaranteeFeePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="StockBasedCompensationAttributableToRedeemableNoncontrollingInterest" id="axti_StockBasedCompensationAttributableToRedeemableNoncontrollingInterest" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="EffectOfForeignCurrencyTranslationOnRedeemableNoncontrollingInterests" id="axti_EffectOfForeignCurrencyTranslationOnRedeemableNoncontrollingInterests" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ChaoyangXinmeiMember" id="axti_ChaoyangXinmeiMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NonControllingInterestsInvestmentsInSubsidiary" id="axti_NonControllingInterestsInvestmentsInSubsidiary" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationOfSubsidiary" id="axti_AdjustmentsToAdditionalPaidInCapitalShareBasedCompensationOfSubsidiary" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="InvestmentInSubsidiaryFromNonControllingInterest" id="axti_InvestmentInSubsidiaryFromNonControllingInterest" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ScenarioPerformanceFinancialMetricLessThan50Member" id="axti_ScenarioPerformanceFinancialMetricLessThan50Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ScenarioPerformanceFinancialMetricIsBetween50To200Member" id="axti_ScenarioPerformanceFinancialMetricIsBetween50To200Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AnnualRevenueGrowthRatePercentage" id="axti_AnnualRevenueGrowthRatePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ScenarioPerformanceFinancialMetricGreaterThan200Member" id="axti_ScenarioPerformanceFinancialMetricGreaterThan200Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankOfBeijingMember" id="axti_BankOfBeijingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="IndustrialBankMember" id="axti_IndustrialBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ChaoYangShuoMeiHighPuritySemiconductorMaterialsCoLtdMember" id="axti_ChaoYangShuoMeiHighPuritySemiconductorMaterialsCoLtdMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ChaoYangTongmeiXtalTechnologyCoLtdMember" id="axti_ChaoYangTongmeiXtalTechnologyCoLtdMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ProceedsFromCapitalIncreaseInSubsidiarySharesFromNoncontrollingInterest" id="axti_ProceedsFromCapitalIncreaseInSubsidiarySharesFromNoncontrollingInterest" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ChaoYangJinMeiGalliumLtd.Member" id="axti_ChaoYangJinMeiGalliumLtd.Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LoanProceedsPaidDirectlyToThirdPartyIncludedInAccountsPayable" id="axti_LoanProceedsPaidDirectlyToThirdPartyIncludedInAccountsPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="SaleOfLandAndBuildingToUnconsolidatedJointVenture" id="axti_SaleOfLandAndBuildingToUnconsolidatedJointVenture" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="JointVentureAgreementsFurtherInvestment" id="axti_JointVentureAgreementsFurtherInvestment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ChaoyangKaimeiQuartzCoLtdMember" id="axti_ChaoyangKaimeiQuartzCoLtdMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ProceedsFromLongTermLoanFromNoncontrollingInterest" id="axti_ProceedsFromLongTermLoanFromNoncontrollingInterest" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="NingboBankMember" id="axti_NingboBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NanjingBankMember" id="axti_NanjingBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.9PercentOneMarch2022DueDateTwoMember" id="axti_BankLoanWith3.9PercentOneMarch2022DueDateTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.6PercentJanuary2022DueDateMember" id="axti_BankLoanWith4.6PercentJanuary2022DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4PercentSeptember2022DueDateMember" id="axti_BankLoanWith4PercentSeptember2022DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4PercentNovember2022DueDateMember" id="axti_BankLoanWith4PercentNovember2022DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.2PercentDecember2022DueDateMember" id="axti_BankLoanWith4.2PercentDecember2022DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.2PercentMay2023DueDateMember" id="axti_BankLoanWith4.2PercentMay2023DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.4PercentJune2023DueDateMember" id="axti_BankLoanWith4.4PercentJune2023DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.4PercentSeptember2023DueDateMember" id="axti_BankLoanWith4.4PercentSeptember2023DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.8PercentAugust2023DueDateMember" id="axti_BankLoanWith4.8PercentAugust2023DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.8PercentSeptember2023DueDateMember" id="axti_BankLoanWith4.8PercentSeptember2023DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.2PercentJuly2023DueDateMember" id="axti_BankLoanWith3.2PercentJuly2023DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.3PercentSeptember2023DueDateMember" id="axti_BankLoanWith4.3PercentSeptember2023DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.9PercentDecember2022DueDateMember" id="axti_BankLoanWith3.9PercentDecember2022DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.8PercentMarch2023DueDateMember" id="axti_BankLoanWith4.8PercentMarch2023DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith2.7PercentMarch2023DueDateMember" id="axti_BankLoanWith2.7PercentMarch2023DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.2PercentApril2023DueDateMember" id="axti_BankLoanWith4.2PercentApril2023DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.3PercentJanuary2023DueDateTwoMember" id="axti_BankLoanWith3.3PercentJanuary2023DueDateTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.5PercentNovember2023DueDateMember" id="axti_BankLoanWith4.5PercentNovember2023DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.5PercentDecember2023DueDateMember" id="axti_BankLoanWith4.5PercentDecember2023DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.3PercentNovember2023DueDateMember" id="axti_BankLoanWith4.3PercentNovember2023DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.6PercentMay2023DueDateMember" id="axti_BankLoanWith3.6PercentMay2023DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.8PercentJune2023DueDateOneMember" id="axti_BankLoanWith4.8PercentJune2023DueDateOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="MinorityInvestorsMember" id="axti_MinorityInvestorsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PrcSubsidiariesAndPrcRawMaterialJointVenturesMember" id="axti_PrcSubsidiariesAndPrcRawMaterialJointVenturesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NumberOfSharesEligibleToVest" id="axti_NumberOfSharesEligibleToVest" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="DecreaseInAdditionalPaidInCapitalInvestmentInSubsidiaryWithNoncontrollingInterest" id="axti_DecreaseInAdditionalPaidInCapitalInvestmentInSubsidiaryWithNoncontrollingInterest" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="BankLoanWith2.8PercentOneMarch2024DueDateOneMember" id="axti_BankLoanWith2.8PercentOneMarch2024DueDateOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.3PercentJanuary2024DueDateTwoMember" id="axti_BankLoanWith3.3PercentJanuary2024DueDateTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith2.4PercentJanuary2024DueDateMember" id="axti_BankLoanWith2.4PercentJanuary2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.5PercentJanuary2024DueDateTwoMember" id="axti_BankLoanWith3.5PercentJanuary2024DueDateTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.8PercentJune2023DueDateMember" id="axti_BankLoanWith4.8PercentJune2023DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestedInPeriod" id="axti_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestedInPeriod" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformanceTargetCapPercentage" id="axti_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformanceTargetCapPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="ScenarioPerformanceMinimumFinancialMetricMember" id="axti_ScenarioPerformanceMinimumFinancialMetricMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FairValueAssetLevel1ToLevel2TransfersAmount" id="axti_FairValueAssetLevel1ToLevel2TransfersAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="FairValueTransferBetweenLevel1AndLevel2DescriptionAndPolicyAbstract" id="axti_FairValueTransferBetweenLevel1AndLevel2DescriptionAndPolicyAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ScheduleOfGainLossOnSaleAndRemeasurementOfEquityMethodInvestmentsTableTextBlock" id="axti_ScheduleOfGainLossOnSaleAndRemeasurementOfEquityMethodInvestmentsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="EquityMethodInvestmentsSaleForeignIncomeTaxWithholding" id="axti_EquityMethodInvestmentsSaleForeignIncomeTaxWithholding" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="EquityMethodInvestmentAmountRetainedCarryingValue" id="axti_EquityMethodInvestmentAmountRetainedCarryingValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="GainLossOnRetainedEquityMethodInvestmentsRemeasurement" id="axti_GainLossOnRetainedEquityMethodInvestmentsRemeasurement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="June2023BankLoanOneMember" id="axti_June2023BankLoanOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="June2023BankLoanTwoMember" id="axti_June2023BankLoanTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.2PercentMay2024DueDateMember" id="axti_BankLoanWith3.2PercentMay2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.2PercentFebruary2024DueDateMember" id="axti_BankLoanWith3.2PercentFebruary2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.8PercentMay2024DueDateMember" id="axti_BankLoanWith3.8PercentMay2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="EquityMethodInvestmentsSaleConsiderationFairValue" id="axti_EquityMethodInvestmentsSaleConsiderationFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="BankLoanWith4.3PercentJune2024DueDateMember" id="axti_BankLoanWith4.3PercentJune2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PercentageOfEquityInterestSold" id="axti_PercentageOfEquityInterestSold" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="BankLoanWith3.6PercentSeptember2024DueDateMember" id="axti_BankLoanWith3.6PercentSeptember2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith2.7PercentSeptember2024DueDateMember" id="axti_BankLoanWith2.7PercentSeptember2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.8PercentMay2024DueDateOneMember" id="axti_BankLoanWith3.8PercentMay2024DueDateOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.3PercentJuly2024DueDateMember" id="axti_BankLoanWith4.3PercentJuly2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.3PercentSeptember2024DueDateMember" id="axti_BankLoanWith4.3PercentSeptember2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.2PercentSeptember2024DueDateMember" id="axti_BankLoanWith4.2PercentSeptember2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.3PercentSeptember2024DueDateMember" id="axti_BankLoanWith3.3PercentSeptember2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AdditionalInvestmentOfJointVentureAgreement" id="axti_AdditionalInvestmentOfJointVentureAgreement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="SubsidiesFromChineseGovernmentMember" id="axti_SubsidiesFromChineseGovernmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ProceedsFromGrantReceivable" id="axti_ProceedsFromGrantReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationForeignIncomeInclusion" id="axti_EffectiveIncomeTaxRateReconciliationForeignIncomeInclusion" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ProceedsFromLoanByNotes" id="axti_ProceedsFromLoanByNotes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="BankLoanWith3.5PercentNovember2024DueDateOneMember" id="axti_BankLoanWith3.5PercentNovember2024DueDateOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.5PercentNovember2024DueDateTwoMember" id="axti_BankLoanWith3.5PercentNovember2024DueDateTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.0PercentDecember2024DueDateMember" id="axti_BankLoanWith3.0PercentDecember2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.3PercentNovember2024DueDateMember" id="axti_BankLoanWith4.3PercentNovember2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.3PercentDecember2024DueDateMember" id="axti_BankLoanWith4.3PercentDecember2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.8PercentOctober2024DueDateMember" id="axti_BankLoanWith3.8PercentOctober2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith2.7PercentDecember2024DueDateMember" id="axti_BankLoanWith2.7PercentDecember2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.3PercentMay2024DueDateMember" id="axti_BankLoanWith3.3PercentMay2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith3.0PercentMay2024DueDateMember" id="axti_BankLoanWith3.0PercentMay2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BankLoanWith4.2PercentOneJanuary2024DueDateMember" id="axti_BankLoanWith4.2PercentOneJanuary2024DueDateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
</xsd:schema>
