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Exhibit 10.17

Lynnette C. Fallon
Executive Vice President HR/Legal and General Counsel
Tel: (978) 787-4120
Fax: (978) 787-4090

                                        
                                                    February 10, 2012

Mary G. Puma, Chairman and Chief Executive Officer
Axcelis Technologies, Inc.
108 Cherry Hill Drive
Beverly, Massachusetts 01915

        Re: Base Compensation of Chief Executive Officer and Chairman

Dear Mary:

        This letter extends the arrangement between Axcelis Technologies, Inc.
and you regarding your base pay increase approved by the Compensation Committee
on April 26, 2011. We have agreed to further defer the implementation of this
increase until January 1, 2013.

        Notwithstanding the delay in effectiveness of this salary increase, in
the event that you are at any time entitled to separation pay under your
Employment Agreement or your Change of Control Agreement with the Company, both
dated as of November 6, 2007, your base compensation rate will be deemed to be
the rate approved by the Compensation Committee on April 26, 2011 and all
amounts due to you shall be calculated as if such increase had become effective
on May 1, 2011 as initially contemplated by the Compensation Committee.

        Please sign below to indicate your agreement to the foregoing. Thank
you.

    Best regards,
 
 
AXCELIS TECHNOLOGIES, INC.
 
 
By:
 
/s/ LYNNETTE C. FALLON

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Lynnette C. Fallon
Executive Vice President HR/Legal and General Counsel

ACCEPTED AND AGREED:    
/s/ MARY G. PUMA

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Mary G. Puma
 
 

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Exhibit 10.17