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                                                                   EXHIBIT 31.2

                                  CERTIFICATION

                       OF THE PRINCIPAL FINANCIAL OFFICER

                      PURSUANT TO RULE 13A-14(A)/15D-14(A)
              (IMPLEMENTING SECTION 302 OF THE SARBANES-OXLEY ACT)

I, Stephen G. Bassett, certify that:

         1. I have reviewed this annual report on Form 10-K of Axcelis
Technologies, Inc.;

         2. Based on my knowledge, this report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to make
the statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this report;

         3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects the
financial condition, results of operations and cash flows of the company as of,
and for, the periods presented in this report;

4. The company's other certifying officer(s) and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial
reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the
company and have:

        (a) Designed such disclosure controls and procedures, or caused such
            disclosure controls and procedures to be designed under our
            supervision, to ensure that material information relating to the
            company, including its consolidated subsidiaries, is made known to
            us by others within those entities, particularly during the period
            in which this report is being prepared;

        (b) Designed such internal control over financial reporting, or caused
            such internal control over financial reporting to be designed under
            our supervision, to provide reasonable assurance regarding the
            reliability of financial reporting and the preparation of financial
            statements for external purposes in accordance with generally
            accepted accounting principles;

        (c) Evaluated the effectiveness of the company's disclosure controls and
            procedures and presented in this report our conclusions about the
            effectiveness of the disclosure controls and procedures, as of the
            end of the period covered by this report based on such evaluation;
            and

        (d) Disclosed in this report any change in the company's internal
            control over financial reporting that occurred during the company's
            most recent fiscal

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            quarter (the registrant's fourth fiscal quarter in the case of an
            annual report) that has materially affected, or is reasonably likely
            to materially affect, the company's internal control over financial
            reporting; and

         5. The company's other certifying officer(s) and I have disclosed,
based on our most recent evaluation of internal control over financial
reporting, to the company's auditors and the audit committee of the company's
board of directors (or persons performing the equivalent functions):

        (a) All significant deficiencies and material weaknesses in the design
            or operation of internal control over financial reporting which are
            reasonably likely to adversely affect the company's ability to
            record, process, summarize and report financial information; and

        (b) Any fraud, whether or not material, that involves management or
            other employees who have a significant role in the registrant's
            internal control over financial reporting.


Date: March 11, 2005                 /s/ Stephen G. Bassett
                                     -------------------------------------------
                                     Stephen G. Bassett, Chief Financial Officer
                                     and Senior Vice President