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                                                                 Exhibit 99.A.3



                 AMENDMENT TO PREFERRED SHARES RIGHTS AGREEMENT

      Amendment dated November 19, 1998 ("Amendment") to the Preferred Shares
Rights Agreement ("Agreement"), dated as of March 5, 1997, between Integrated
Process Equipment Corp., a Delaware corporation (the "Company"), and American
Stock Transfer & Trust Company, a national banking association (the "Rights
Agent").

      In compliance with the terms of Section 27 of the Agreement, this
Amendment is being executed by the Company and the Rights Agent for the purpose
of amending the Agreement as set forth below:

      The Agreement is hereby amended as follows:

      1. Section 1(a) shall be amended by deleting the word "and" immediately
preceding subsection (ii) and inserting the following at the end of Section
1(a):

            "and (iii) none of SpeedFam, Inc. ("Merger Sub"), SpeedFam
            International, Inc. ("SpeedFam"), SpeedFam's subsidiaries, or
            SpeedFam's permitted assignees or transferees under that certain
            Company Stock Option Agreement of even date herewith in favor of
            SpeedFam (the "Company Stock Option Agreement") is or will become an
            Acquiring Person pursuant to this Agreement by reason of the
            execution of the Agreement and Plan of Merger of even date herewith
            by and among the Company, SpeedFam and Merger Sub (the "Merger
            Agreement") or the Company Stock Option Agreement or the SpeedFam
            Stock Option Agreement of even date herewith in favor of the Company
            (the "SpeedFam Stock Option Agreement" and, together with the
            Company Stock Option Agreement, the "Stock Option Agreements") or
            the consummation of any of the transactions contemplated by the
            Merger Agreement or the Stock Option Agreements or the consummation
            of the merger contemplated by the Merger Agreement (the "Merger"),
            or the consummation of any of the other transactions contemplated by
            the Merger Agreement or the Stock Option Agreements."

      2. Section 1(m) shall be amended by inserting the following at the end of
Section 1(m):

            "Notwithstanding the foregoing or any provision to the contrary in
            this Agreement, a Distribution Date shall not occur by reason of the
            execution of the Merger Agreement or either of the Stock Option
            Agreements or the consummation of any of the transactions
            contemplated by the Merger Agreement or the Stock Option Agreements
            or the consummation of the Merger, or the consummation of any of the
            other transactions contemplated by the Merger Agreement or the Stock
            Option Agreements."

      3. Section 1(s) shall be amended and restated in its entirety to read as
follows:


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            "(s) 'Final Expiration Date' shall mean the earlier of (i) the day
            preceding the day upon which the Effective Time (as defined in the
            Merger Agreement) of the Merger occurs or (ii) January 23, 2007."

      4. Section 1(x) shall be amended and restated in its entirety to read as
follows:

            "(x) 'Preferred Shares' shall mean shares of Series D Participating
            Preferred Stock, $0.01 par value, of the Company."

      5. Section 1(jj) shall be amended by inserting the following at the end of
Section 1(jj):

            "Notwithstanding the foregoing or any provision to the contrary in
            this Agreement, a Shares Acquisition Date shall not occur by reason
            of the execution of the Merger Agreement or either of the Stock
            Option Agreements or the consummation of any of the transactions
            contemplated by the Merger Agreement or the Stock Option Agreements
            or the consummation of the Merger, or the consummation of any of the
            other transactions contemplated by the Merger Agreement or the Stock
            Option Agreements."

      6. Section 1(qq) shall be amended by inserting the following at the end of
Section 1(qq):

            "Notwithstanding the foregoing or any provision to the contrary in
            this Agreement, a Triggering Event shall not occur by reason of the
            execution of the Merger Agreement or either of the Stock Option
            Agreements or the consummation of any of the other transactions
            contemplated by the Merger Agreement or the Stock Option Agreements
            or the consummation of the Merger, or the consummation of any of the
            other transactions contemplated by the Merger Agreement or the Stock
            Option Agreements."

      7.    (a)   This Amendment may not be further amended by the Company
                  without the prior written consent of SpeedFam in its sole
                  discretion.

            (b)   This Amendment shall be deemed to be entered into under the
                  laws of the State of Delaware and for all purposes shall be
                  governed by and construed in accordance with the laws of such
                  State applicable to contracts to be made and performed
                  entirely within such State.

            (c)   This Amendment may be executed in any number of counterparts
                  and each of such counterparts shall for all purposes be deemed
                  to be an original, and all such counterparts shall together
                  constitute but one and the same instrument.


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      8. As amended hereby, the Agreement shall remain in full force and effect.


Integrated Process Equipment Corp.

By: /s/ John S. Hodgson,
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        John S. Hodgson,
        VP and CFO

      Attest: /s/ Roger D. McDaniel,
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                  Roger D. McDaniel,
                  President and CEO


American Stock Transfer & Trust Company
as Rights Agent

By:    /s/ Herbert J. Lemmer
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Name:  HERBERT J. LEMMER
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Title: VICE PRESIDENT
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