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                                                                      Exhibit 10


                         AMENDMENT NO. 1 TO AMENDED AND

                       RESTATED REVOLVING CREDIT AGREEMENT


      THIS AMENDMENT NO. 1 TO AMENDED AND RESTATED REVOLVING CREDIT AGREEMENT is
made as of January 25, 1998, by and among SPEEDFAM INTERNATIONAL, INC., an
Illinois corporation (the "Borrower"), THE FIRST NATIONAL BANK OF CHICAGO
("First Chicago"), a national banking association, FIRSTAR BANK MILWAUKEE, N.A.
("Firstar"), a national banking association, BANK OF AMERICA NATIONAL TRUST AND
SAVINGS ASSOCIATION ("BA"), a national banking association, and NORWEST BANK
ARIZONA, N.A. ("Norwest"), a national banking association, (First Chicago,
Firstar in its capacity as a bank, BA and Norwest shall be collectively referred
to as the "Banks"), and Firstar in its capacity as agent for the Banks (the
"Agent").

      In consideration of the mutual covenants, conditions and agreements set
forth herein, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, it is hereby agreed that:


                                    ARTICLE I
                                   DEFINITIONS

      When used herein, the following terms shall have the following meanings
specified:

      1.1 "Amendment" shall mean this Amendment No. 1 to Amended and Restated
Revolving Credit Agreement.

      1.2 "Credit Agreement" shall mean the Amended and Restated Revolving
Credit Agreement dated as of August 29, 1997, as amended by this Amendment.


                                   ARTICLE II
                                   AMENDMENTS

      The Credit Agreement is amended as follows:

      2.1 Section 6.5 -- Restricted Payments. Section 6.5 of the Credit
Agreement is hereby amended by replacing the period at the end of Section 6.5
with the following:

      "and (c) the Company may redeem (the "Redemption") up to ten percent (10%)
      of the common stock of the Company outstanding as of December 31, 1997,
      provided that all such redemptions shall occur on or before December 31,
      1999."

      2.2 Section 6.8 -- Net Worth. Section 6.8 of the Credit Agreement is
hereby amended in its entirety as follows:
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            "6.8 Net Worth. Permit the Net worth of the Company at any time to
      be less than (a) $125,000,000 plus (b) all net proceeds from the issuance
      of shares of all capital stock of the Company after August 29, 1997 on a
      cumulative basis plus (c) 50% of the Company's Net Income (but not Net
      Loss) for each fiscal year of the Company ending after May 31, 1997 on a
      cumulative basis minus (d) the lesser of (i) $30,000,000 or (ii) the
      aggregate amount paid by the Company to repurchase its common stock
      pursuant to the Redemption"

      2.3 Miscellaneous Amendments. The Credit Agreement, the Notes, the
Related Documents and all other agreements and instruments executed and
delivered heretofore or hereafter pursuant to the Credit Agreement are amended
hereby so that any reference therein to the Credit Agreement shall be deemed to
be a reference to such agreements and instruments as amended by or pursuant to
this Amendment.


                                   ARTICLE III
                         REPRESENTATIONS AND WARRANTIES

      The Borrower hereby represents and warrants to the Banks and Agent that:

      3.1 Credit Agreement. All of the representations and warranties made by
the Borrower in the Credit Agreement are true and correct on the date of this
Amendment.

      3.2 Authorization; Enforceability. The making, execution and delivery of
this Amendment and performance of and compliance with the terms of the Credit
Agreement, as amended, have been duly authorized by all necessary corporate
action by the Borrower. This Amendment is the valid and binding obligation of
the Borrower, enforceable against the Borrower in accordance with its terms.

      3.3 Absence of Conflicting Obligations. The making, execution and delivery
of this Amendment and performance of and compliance with the terms of the Credit
Agreement, as amended, do not violate any presently existing provision of law or
the articles or certificate of incorporation or bylaws of the Borrower or any
agreement to which the Borrower is a party or by which it or any of its assets
is bound.


                                   ARTICLE IV
                                  MISCELLANEOUS

      4.1 Continuance of Credit Agreement. Except as specifically amended by
this Amendment, the Credit Agreement shall remain in full force and effect.


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      4.2 Survival. All agreements, representations and warranties made in this
Amendment or in any documents delivered pursuant to this Amendment shall survive
the execution of this Amendment and the delivery of any such document.

      4.3 Governing Law. This Amendment shall be governed by, and construed and
interpreted in accordance with, the laws of the State of Wisconsin applicable to
agreements made and wholly performed within such state.

      4.4 Counterparts; Headings. This Amendment may be executed in several
counterparts, each of which shall be deemed an original, but such counterparts
shall together constitute but one and the same agreement. Article and section
headings in this Amendment are inserted for convenience of reference only and
shall not constitute a part hereof.

      4.5 Severability. Any provision of this Amendment which is prohibited or
unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective
to the extent of such prohibition or unenforceability without invalidating the
remaining provisions of this Amendment in such jurisdiction or affecting the
validity or enforceability of any provision in any other jurisdiction.

      4.6 Conditions. The effectiveness of this Amendment is subject to the
Banks and Agent having received on or before the date hereof such additional
supporting documents and materials as the Banks and Agent may reasonably
request.

      4.7 Other Capitalized Terms. All capitalized terms used in this Amendment
and not specifically defined herein shall have the definitions assigned to such
terms in the Credit Agreement.

                         [SIGNATURES ON FOLLOWING PAGE]


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      IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 1
to Amended and Restated Revolving Credit Agreement as of the day and year first
written above.

                                  SPEEDFAM INTERNATIONAL, INC.
                                
                                
                                  By: /s/ Roger K. Marach
                                      ---------------------------------------
                                      Roger K. Marach, Treasurer and CFO
                                
                                  FIRSTAR MILWAUKEE, N.A.
                                
                                
                                  By: /s/ James A. Meyer
                                      ---------------------------------------
                                      James A. Meyer, Vice President
                                
                                  THE FIRST NATIONAL BANK OF CHICAGO
                                
                                
                                  By: /s/ James D. Benkow
                                      ---------------------------------------
                                      James D. Benkow, Vice President
                                
                                  BANK OF AMERICA NATIONAL TRUST
                                    AND SAVINGS ASSOCIATION
                                
                                
                                  By: /s/ Kevin McMahon
                                      ---------------------------------------
                                      Kevin McMahon, Managing Director
                                
                                  NORWEST BANK ARIZONA, N.A.
                                
                                
                                  By: /s/ Mae G. DelaBarre
                                      ---------------------------------------
                                      Mae G. DelaBarre, Assistant Vice President
                                
                                  FIRSTAR BANK MILWAUKEE, N.A., as agent
                                
                                
                                  By: /s/ Stephen E. Carlton
                                      ---------------------------------------   
                                      Stephen E. Carlton, vice President        
                    

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