<SEC-DOCUMENT>0001415889-25-013646.txt : 20250519
<SEC-HEADER>0001415889-25-013646.hdr.sgml : 20250519
<ACCEPTANCE-DATETIME>20250519163029
ACCESSION NUMBER:		0001415889-25-013646
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20250515
FILED AS OF DATE:		20250519
DATE AS OF CHANGE:		20250519

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Redinbo Greg
		CENTRAL INDEX KEY:			0001940017
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-30941
		FILM NUMBER:		25964454

	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
		EIN:				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>
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<TYPE>4
<SEQUENCE>1
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    <periodOfReport>2025-05-15</periodOfReport>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001940017</rptOwnerCik>
            <rptOwnerName>Redinbo Greg</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>false</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>EVP MARKETING AND APPLICATIONS</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>0</aff10b5One>

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                <transactionFormType>4</transactionFormType>
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                    <value>28031</value>
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    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2025.  Assuming continuation of employment, these restricted stock units will vest as to 25% of the shares granted on each of May 15, 2026, May 15, 2027, May 15, 2028, and May 15, 2029.</footnote>
        <footnote id="F2">Of the shares held following this grant on May 15, 2025, 18,133 were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture.</footnote>
        <footnote id="F3">These shares are issuable on vesting of restricted stock units granted under the Company's 2012 Equity Incentive Plan on May 15, 2025.  In this grant, the executive may earn shares of common stock, ranging from zero to 150% of the granted units. The shares are earned based on the achievement of 2025 performance goals. Assuming continuation of employment, 50% of the earned shares will vest on February 28, 2027, and 50% of the earned shares will vest on February 28, 2028. Unearned restricted stock units will forfeit on February 28, 2026.</footnote>
        <footnote id="F4">Of the shares held after this grant on May 15, 2025, 24,281 shares were issuable on vesting of restricted stock units granted to the executive under the 2012 Equity Incentive Plan and are subject to forfeiture.</footnote>
        <footnote id="F5">This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2025 of service vesting restricted stock units granted to the executive in May 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 restricted stock units.</footnote>
        <footnote id="F6">Represents the closing price of the common stock on the date of the tax withholding.</footnote>
        <footnote id="F7">Of the shares held after this vesting event on May 15, 2025, 23,569 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="F8">This forfeiture of shares for tax withholding purposes relates to the vesting on May 15, 2025 of service vesting restricted stock units granted to the executive in May 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 restricted stock units.</footnote>
        <footnote id="F9">Of the shares held after this vesting event on May 15, 2025, 22,968 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/ Eileen J. Evans, Attorney-in-Fact</signatureName>
        <signatureDate>2025-05-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
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<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>ex24-05192025_040525.htm
<TEXT>
<!DOCTYPE html PUBLIC "-//IETF//DTD HTML//EN">
<html><head><title>ex24-05192025_040525.htm</title></head><body style="margin-top:0;font-family:Times New Roman; font-size:10pt; color:#000000">
<p style="margin:0px" align="center">Exhibit 24.1</p>
<p style="margin:0px" align="center"><br></p>
<p style="margin:0px" align="center">POWER OF ATTORNEY</p>
<p style="margin:0px" align="center">For Executing Reports under Section 16(a)</p>
<p style="margin:0px" align="center">with respect to securities of</p>
<p style="margin:0px" align="center">AXCELIS TECHNOLOGIES INC.</p>
<p style="margin:0px" align="center">&nbsp;</p>
<p style="margin:0px; text-indent:48px">The undersigned hereby constitutes and appoints each of Russell J. Low, James G. Coogan, Eileen J. Evans, Lynnette C. Fallon, and Megan Gates, Esq. of the Covington &amp; Burling law firm, each acting singly, the undersigned<font style="font-family:Arial Unicode MS,Times New Roman">&rsquo;</font>s true and lawful attorney-in-fact, from the date hereof until this Power of Attorney is revoked, to:</p>
<p style="margin:0px; text-indent:48px" align="justify">&nbsp;</p>
<p style="margin-top:0px; margin-bottom:-2px; text-indent:0.467px; width:48px; float:left">(1)</p>
<p style="margin:0px; padding-left:48px; text-indent:-2px">execute, for and on behalf of the undersigned, Forms 3, 4 and 5 with respect to securities of Axcelis Technologies, Inc. in accordance with Section 16(a) of the Securities Exchange Act of 1934 and the rules thereunder, it being understood that the documents executed by such attorney-in-fact on behalf of the undersigned pursuant to this Power of Attorney shall be in such form and shall contain such terms and conditions as such attorney-in-fact may approve in his or her discretion; and</p>
<p style="margin:0px; clear:left">&nbsp;</p>
<p style="margin-top:0px; margin-bottom:-2px; text-indent:0.467px; width:48px; float:left">(2)</p>
<p style="margin:0px; padding-left:48px; text-indent:-2px">do and perform any and all acts, for and on behalf of the undersigned, that may be necessary or desirable to complete the execution of any such Form 3, 4 or 5 and the timely filing of such form with the United States Securities and Exchange Commission and any other authority.</p>
<p style="margin:0px; clear:left">&nbsp;</p>
<p style="margin:0px; text-indent:48px">The undersigned hereby grants to each such attorney-in-fact full power and authority to do and perform all and every act and thing whatsoever requisite, necessary and proper to be done in the exercise of any of the rights and powers herein granted, as fully for all intents and purposes as the undersigned might or could do if personally present, with full power of substitution or revocation, hereby ratifying and confirming all that such attorney-in-fact, or his or her substitute or substitutes, shall lawfully do or cause to be done by virtue of this power of attorney and the rights and powers herein granted. The undersigned acknowledges that the foregoing attorneys-in-fact, in serving in such capacity at the request of the undersigned, are not assuming any of the undersigned<font style="font-family:Arial Unicode MS,Times New Roman">&rsquo;</font>s responsibilities to comply with Section 16 of the Securities Exchange Act of 1934.</p>
<p style="margin:0px; text-indent:48px">&nbsp;</p>
<p style="margin:0px; text-indent:48px">IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be executed this 8th day of May, 2025.</p>
<p style="margin:0px">&nbsp;</p>
<p style="margin:0px"><br></p>
<table style="margin-top:0px; font-size:10pt" cellpadding="0" cellspacing="0" width="100%" align="center"><tr style="font-size:0"><td width="166.667"></td><td width="166.667"></td></tr><tr><td style="margin-top:0px; padding-left:4px; padding-top:0px; padding-right:4px; padding-bottom:0px" valign="bottom" width="166.667"><p style="margin:0px">&nbsp;</p>
</td><td style="margin-top:0px; padding-left:4px; padding-top:0px; padding-right:4px; padding-bottom:0px; border-bottom:1.333px solid #000000" valign="bottom" width="166.667"><p style="margin:0px">/s/ Gregory F. Redinbo</p>
</td></tr><tr><td style="margin-top:0px; padding-left:4px; padding-top:0px; padding-right:4px; padding-bottom:0px" valign="bottom" width="166.667"><p style="margin:0px">&nbsp;</p>
</td><td style="margin-top:0px; padding-left:4px; padding-top:0px; padding-right:4px; padding-bottom:0px" valign="bottom" width="166.667"><p style="margin:0px">Gregory F. Redinbo</p>
</td></tr></table><p style="margin:0px">&nbsp;</p>
<p style="margin-top:0px; margin-bottom:6.667px">&nbsp;</p>
<p style="margin:0px">&nbsp;</p>
<p style="margin:0px"><br></p>
<p style="margin:0px"><br></p>
</body></html>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
