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  <xsd:element id="acls_UnrecognizedTaxBenefitsRecordedAsOtherLongTermLiability" name="UnrecognizedTaxBenefitsRecordedAsOtherLongTermLiability" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="acls_UnrecognizedTaxBenefitsRecordedAsDecreaseInDeferredTaxAssetsAndOffsettingValuationAllowance" name="UnrecognizedTaxBenefitsRecordedAsDecreaseInDeferredTaxAssetsAndOffsettingValuationAllowance" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element name="AssetsManufacturedForInternalUseMember" id="acls_AssetsManufacturedForInternalUseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EmployeeStockPurchasePlanAbstract" id="acls_EmployeeStockPurchasePlanAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPayrollDeductionsAsPercentageOfEmployeesSalary" id="acls_ShareBasedCompensationArrangementByShareBasedPaymentAwardPayrollDeductionsAsPercentageOfEmployeesSalary" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOfferingPeriodOverWhichCompensationExpenseIsAmortized" id="acls_ShareBasedCompensationArrangementByShareBasedPaymentAwardOfferingPeriodOverWhichCompensationExpenseIsAmortized" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsForfeitureRate" id="acls_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsForfeitureRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="EmployeesMember" id="acls_EmployeesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element id="acls_NonEmployeeMemberOfBoardOfDirectorMember" name="NonEmployeeMemberOfBoardOfDirectorMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element name="RegularEmployeesMember" id="acls_RegularEmployeesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element id="acls_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensationNoncurrent" name="DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensationNoncurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element name="StockOptionAwardsMember" id="acls_StockOptionAwardsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="PropertyPlantAndEquipmentUsefulLivesTableTextBlock" id="acls_PropertyPlantAndEquipmentUsefulLivesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPeriodAfterTerminationToRetiringEmployeesToExerciseVestedAwards" id="acls_ShareBasedCompensationArrangementByShareBasedPaymentAwardPeriodAfterTerminationToRetiringEmployeesToExerciseVestedAwards" type="xbrli:durationItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DefinedContributionPlanLineItems" id="acls_DefinedContributionPlanLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="AccumulatedOtherComprehensiveIncomeLossPolicyTextBlock" id="acls_AccumulatedOtherComprehensiveIncomeLossPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" abstract="false" nillable="true" xbrli:periodType="duration" />
  <xsd:element name="DeferredIncomeTaxExpenseBenefitAfterValuationAllowanceAllocation" id="acls_DeferredIncomeTaxExpenseBenefitAfterValuationAllowanceAllocation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element name="ResearchDevelopmentAndOtherTaxCreditMember" id="acls_ResearchDevelopmentAndOtherTaxCreditMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration" />
  <xsd:element id="acls_AllowanceForDoubtfulAccountsAndReturnsMember" name="AllowanceForDoubtfulAccountsAndReturnsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="acls_ChargesRelatedToReflectLowerOfCostOrMarketValue" name="ChargesRelatedToReflectLowerOfCostOrMarketValue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="acls_DepositRelatingToCustomsActivity" name="DepositRelatingToCustomsActivity" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" abstract="false" />
  <xsd:element id="acls_DeferredTaxAssetsTaxCreditCarryforwardsStateAndLocal" name="DeferredTaxAssetsTaxCreditCarryforwardsStateAndLocal" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="acls_SaleAndLeaseBackMember" name="SaleAndLeaseBackMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="acls_BeverlyPropertyOwnerLlcMember" name="BeverlyPropertyOwnerLlcMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="acls_CashCashEquivalentsAndRestrictedCashTextBlock" name="CashCashEquivalentsAndRestrictedCashTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="acls_CashCashEquivalentsAndRestrictedCashTableTextBlock" name="CashCashEquivalentsAndRestrictedCashTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="acls_MoneyMarketFundsUsGovernmentSecuritiesAndAgencyInvestmentsMember" name="MoneyMarketFundsUsGovernmentSecuritiesAndAgencyInvestmentsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="acls_ProvisionForExcessAndObsoleteInventory" name="ProvisionForExcessAndObsoleteInventory" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="acls_ServicesMember" name="ServicesMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="acls_AfterMarketMember" name="AfterMarketMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="acls_PercentageOfPaymentUponShipmentOfTool" name="PercentageOfPaymentUponShipmentOfTool" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" abstract="false" />
  <xsd:element id="acls_PeriodOfPaymentUponDeliveryOfParts" name="PeriodOfPaymentUponDeliveryOfParts" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="acls_PercentageOfPaymentUponInstallation" name="PercentageOfPaymentUponInstallation" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" abstract="false" />
  <xsd:element id="acls_RevenueFromExternalCustomersByDisciplineAreasTableTextBlock" name="RevenueFromExternalCustomersByDisciplineAreasTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="acls_PeriodOfUnsatisfiedExtendedWarrantyPerformanceObligations" name="PeriodOfUnsatisfiedExtendedWarrantyPerformanceObligations" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="acls_ExtendedProductWarrantyPeriod" name="ExtendedProductWarrantyPeriod" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="acls_RecognizingAssetsRelatedToRecoverableCustomerContractCostsPolicyTextBlock" name="RecognizingAssetsRelatedToRecoverableCustomerContractCostsPolicyTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="acls_AssetsManufacturedForInternalUseDisclosureTextBlock" name="AssetsManufacturedForInternalUseDisclosureTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="acls_InternalUsedAssetsTypeAxis" name="InternalUsedAssetsTypeAxis" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="acls_InternalUsedAssetsTypeDomain" name="InternalUsedAssetsTypeDomain" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="acls_CompletedInternalUseAssetsMember" name="CompletedInternalUseAssetsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="acls_NewSystemsRevenueMember" name="NewSystemsRevenueMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="acls_LeaseDisclosureTextBlock" name="LeaseDisclosureTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="acls_OperatingAndFinanceLeaseRightOfUseAsset" name="OperatingAndFinanceLeaseRightOfUseAsset" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="acls_OperatingAndFinanceLeaseLiability" name="OperatingAndFinanceLeaseLiability" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="acls_FinanceLeaseAccumulatedDepreciation" name="FinanceLeaseAccumulatedDepreciation" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="acls_FinanceLeaseCost" name="FinanceLeaseCost" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="acls_LeaseBalanceSheetDisclosureTableTextBlock" name="LeaseBalanceSheetDisclosureTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="acls_LeaseCashFlowInformationDisclosureTableTextBlock" name="LeaseCashFlowInformationDisclosureTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="acls_ShortTermAndVariableLeaseCost" name="ShortTermAndVariableLeaseCost" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="acls_LeaseQuantitativeDisclosureTableTextBlock" name="LeaseQuantitativeDisclosureTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="acls_WeightedAverageRemainingLeaseTermAndDiscountRateAbstract" name="WeightedAverageRemainingLeaseTermAndDiscountRateAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="acls_FinanceAndOperatingLeaseLiabilitiesPaymentsDueAbstract" name="FinanceAndOperatingLeaseLiabilitiesPaymentsDueAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="acls_LesseeOperatingAndFinanceLeaseLiabilityPaymentsDueYearTwo" name="LesseeOperatingAndFinanceLeaseLiabilityPaymentsDueYearTwo" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="acls_LesseeOperatingAndFinanceLeaseLiabilityPaymentsDueYearThree" name="LesseeOperatingAndFinanceLeaseLiabilityPaymentsDueYearThree" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="acls_LesseeOperatingAndFinanceLeaseLiabilityPaymentsDueYearFour" name="LesseeOperatingAndFinanceLeaseLiabilityPaymentsDueYearFour" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="acls_LesseeOperatingAndFinanceLeaseLiabilityPaymentsDueYearFive" name="LesseeOperatingAndFinanceLeaseLiabilityPaymentsDueYearFive" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="acls_LesseeOperatingAndFinanceLeaseLiabilityPaymentsDueAfterYearFive" name="LesseeOperatingAndFinanceLeaseLiabilityPaymentsDueAfterYearFive" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="acls_LesseeOperatingAndFinanceLeaseLiabilityPaymentsDue" name="LesseeOperatingAndFinanceLeaseLiabilityPaymentsDue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="acls_LesseeOperatingAndFinanceLeaseLiabilityUndiscountedExcessAmount" name="LesseeOperatingAndFinanceLeaseLiabilityUndiscountedExcessAmount" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="acls_ContractWithCustomerLiabilityDeferralOfRevenue" name="ContractWithCustomerLiabilityDeferralOfRevenue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" abstract="false" />
  <xsd:element id="acls_DeferredTaxAssetOperatingLeaseLiabilities" name="DeferredTaxAssetOperatingLeaseLiabilities" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="acls_LesseeOperatingAndFinanceLeaseLiabilityPaymentsDueNextTwelveMonths" name="LesseeOperatingAndFinanceLeaseLiabilityPaymentsDueNextTwelveMonths" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="acls_OperatingAndFinanceLeaseLiabilityMaturityTableTextBlock" name="OperatingAndFinanceLeaseLiabilityMaturityTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="acls_ShippingAndHandlingCostsPolicyTextBlock" name="ShippingAndHandlingCostsPolicyTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="acls_NetSettlementOnRestrictedStockGrants" name="NetSettlementOnRestrictedStockGrants" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="acls_IncreaseInInventoryReserves" name="IncreaseInInventoryReserves" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" abstract="false" />
  <xsd:element id="acls_CostOfPropertyRepairsAndMaintenanceCapitalized" name="CostOfPropertyRepairsAndMaintenanceCapitalized" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="acls_DeferredTaxAssetsCapitalizedResearchAndDevelopmentCosts" name="DeferredTaxAssetsCapitalizedResearchAndDevelopmentCosts" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="acls_OperatingLossCarryforwardsAreSubjectToUncertainTaxPositionReserve" name="OperatingLossCarryforwardsAreSubjectToUncertainTaxPositionReserve" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element name="PropertyPlantAndEquipmentOtherUsefulLife" id="acls_PropertyPlantAndEquipmentOtherUsefulLife" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAuthorizedNumberOfSharesApprovedByShareholders" id="acls_ShareBasedCompensationArrangementByShareBasedPaymentAwardAuthorizedNumberOfSharesApprovedByShareholders" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAuthorizedNumberOfSharesFromExpirationsOrForfeituresOfPriorEquityPlan" id="acls_ShareBasedCompensationArrangementByShareBasedPaymentAwardAuthorizedNumberOfSharesFromExpirationsOrForfeituresOfPriorEquityPlan" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ProductOrServiceMember" id="acls_ProductOrServiceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="EarningsPerShareDetailAbstract" id="acls_EarningsPerShareDetailAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PercentageOfPreShipmentDeposit" id="acls_PercentageOfPreShipmentDeposit" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LetterOfCreditAssociatedWithWorkersCompensation" id="acls_LetterOfCreditAssociatedWithWorkersCompensation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DepositRelatingToCustomerPurposes" id="acls_DepositRelatingToCustomerPurposes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="StockReissuedDuringPeriodSharesEmployeeStockPurchasePlans" id="acls_StockReissuedDuringPeriodSharesEmployeeStockPurchasePlans" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="SingleReportableSegmentMember" id="acls_SingleReportableSegmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CustomerNumberMember" id="acls_CustomerNumberMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DebtSecuritiesAvailableForSaleAmortizedCostMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughTwo" id="acls_DebtSecuritiesAvailableForSaleAmortizedCostMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughTwo" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DebtSecuritiesAvailableForSaleFairValueMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughTwo" id="acls_DebtSecuritiesAvailableForSaleFairValueMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughTwo" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ContractWithCustomerLiabilityOtherAdjustments" id="acls_ContractWithCustomerLiabilityOtherAdjustments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="VeecoInstrumentsIncMember" id="acls_VeecoInstrumentsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BusinessCombinationConsiderationTransferredEquityInterestShareIssuedExchangeRatio" id="acls_BusinessCombinationConsiderationTransferredEquityInterestShareIssuedExchangeRatio" type="xbrli:pureItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="BusinessAcquisitionTerminationFeePayableToOtherParty" id="acls_BusinessAcquisitionTerminationFeePayableToOtherParty" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="BusinessAcquisitionTerminationFeeReceivableFromOtherParty" id="acls_BusinessAcquisitionTerminationFeeReceivableFromOtherParty" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="BusinessAcquisitionExpenseReimbursementByNonTerminatingParty" id="acls_BusinessAcquisitionExpenseReimbursementByNonTerminatingParty" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="RussellJ.LowMember" id="acls_RussellJ.LowMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedPaymentArrangementExpenseNetCharge" id="acls_ShareBasedPaymentArrangementExpenseNetCharge" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="StockIssuedDuringPeriodFractionalSharesMerger" id="acls_StockIssuedDuringPeriodFractionalSharesMerger" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="IncomeTaxReconciliationWithholdingTaxAmount" id="acls_IncomeTaxReconciliationWithholdingTaxAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="IncomeTaxReconciliationAllAdjustmentsAmount" id="acls_IncomeTaxReconciliationAllAdjustmentsAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="IncomeTaxRateReconciliationNondeductibleExpenseCompensationAmount" id="acls_IncomeTaxRateReconciliationNondeductibleExpenseCompensationAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationWithholdingTaxPercent" id="acls_EffectiveIncomeTaxRateReconciliationWithholdingTaxPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationAllAdjustmentsPercent" id="acls_EffectiveIncomeTaxRateReconciliationAllAdjustmentsPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseCompensationPercent" id="acls_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseCompensationPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ForeignWithholdTaxesPaidAfterRefundReceived" id="acls_ForeignWithholdTaxesPaidAfterRefundReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="IncomeTaxPaidOtherForeignAfterRefundReceived" id="acls_IncomeTaxPaidOtherForeignAfterRefundReceived" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="DeferredTaxAssetsBusinessTransactionCosts" id="acls_DeferredTaxAssetsBusinessTransactionCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="CashAndCashEquivalentsAndShortTermInvestmentsPolicyTextBlock" id="acls_CashAndCashEquivalentsAndShortTermInvestmentsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LongTermInvestmentsPolicyTextBlock" id="acls_LongTermInvestmentsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
</xsd:schema>
