<SEC-DOCUMENT>0001415889-24-006102.txt : 20240301
<SEC-HEADER>0001415889-24-006102.hdr.sgml : 20240301
<ACCEPTANCE-DATETIME>20240301163019
ACCESSION NUMBER:		0001415889-24-006102
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20240228
FILED AS OF DATE:		20240301
DATE AS OF CHANGE:		20240301

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			PUMA MARY G
		CENTRAL INDEX KEY:			0001158015
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-30941
		FILM NUMBER:		24710401

	MAIL ADDRESS:	
		STREET 1:		AXCELIS TECHNOLOGIES INC.
		STREET 2:		108 CHERRY HILL DRIVE
		CITY:			BEVERLY
		STATE:			MA
		ZIP:			01915

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AXCELIS TECHNOLOGIES INC
		CENTRAL INDEX KEY:			0001113232
		STANDARD INDUSTRIAL CLASSIFICATION:	SPECIAL INDUSTRY MACHINERY, NEC [3559]
		ORGANIZATION NAME:           	06 Technology
		IRS NUMBER:				341818596
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		108 CHERRY HILL DRIVE
		CITY:			BEVERLY
		STATE:			MA
		ZIP:			01915
		BUSINESS PHONE:		978-787-4000

	MAIL ADDRESS:	
		STREET 1:		108 CHERRY HILL DRIVE
		CITY:			BEVERLY
		STATE:			MA
		ZIP:			01915

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	EATON SEMICONDUCTOR EQUIPMENT INC
		DATE OF NAME CHANGE:	20000501
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>form4-03012024_040303.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2024-02-28</periodOfReport>

    <issuer>
        <issuerCik>0001113232</issuerCik>
        <issuerName>AXCELIS TECHNOLOGIES INC</issuerName>
        <issuerTradingSymbol>ACLS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001158015</rptOwnerCik>
            <rptOwnerName>PUMA MARY G</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O AXCELIS TECHNOLOGIES, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>108 CHERRY HILL DRIVE</rptOwnerStreet2>
            <rptOwnerCity>BEVERLY</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>01915</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>true</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>EXECUTIVE CHAIRPERSON</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2024-02-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>6289</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>256198</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2024-02-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F4"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>6828</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>249370</value>
                    <footnoteId id="F5"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Held by Spouse</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">This forfeiture of shares for tax withholding purposes relates to the vesting on February 28, 2024 of the remainder of performance based restricted stock units (&quot;PRSUs&quot;) granted to the executive in May 2022.  These shares were determined to be earned by the executive pursuant to a resolution of the Axcelis Technologies, Inc. Compensation Committee on February 16, 2023, and half of the earned shares vested on February 28, 2023. As agreed with the executive, the shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested PRSUs.</footnote>
        <footnote id="F2">These shares were withheld by the Company to cover the tax withholding obligations of the executive on the vesting of PRSUs on February 28, 2024.</footnote>
        <footnote id="F3">Of the shares held as of February 28, 2024 after the vesting of the 2022 PRSUs and before the vesting of the 2023 PRSUs, 57,447 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture.</footnote>
        <footnote id="F4">This forfeiture of shares for tax withholding purposes relates to the vesting on February 28, 2024 of PRSUs granted to the executive in May 2023.  Of the granted units, 135% were determined to be earned by the executive pursuant to a resolution of the Axcelis Technologies, Inc. Compensation Committee on February 8, 2024, and all of the earned shares vested on February 28, 2024. As agreed with the executive, the shares issued to the executive on the vesting were reduced by a number of shares having a value equal to the executive's tax withholding obligation with respect to the vested PRSUs.</footnote>
        <footnote id="F5">Of the shares held as of February 28, 2024 after the vesting of both the 2022 PRSUs and 2023 PRSUs, 41,223 were issuable on vesting of restricted stock units granted to the reporting person under the 2012 Equity Incentive Plan and are subject to forfeiture.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Lynnette C. Fallon, Attorney-in-Fact</signatureName>
        <signatureDate>2024-02-28</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
