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                                                                   Exhibit 10.37

                       AMENDMENT TO EMPLOYMENT AGREEMENT

This Amendment to Employment Agreement (this "Amendment") is made and entered
into as of April 24, 2001 between Therma-Wave, Inc., a Delaware corporation (the
"Company"), and Martin M. Schwartz ("Executive").

                                   RECITALS:

     A.   The Company and Executive have entered to an Employment Agreement
          dated as of August 3, 1998 (the "Agreement"), which sets forth the
          terms and conditions of Executive's employment by the Company.

     B.   Since July 1999 Executive has served as the President and Chief
          Executive Officer of the Company.

     C.   The Company and Executive desire to amend the Agreement as set forth
          herein.

     In consideration of the continued employment of Executive by the Company,
     the mutual covenants contained herein, and other good and valuable
     consideration, the receipt and sufficiency of which are hereby
     acknowledged, the parties hereto agree as follows:

     1.     Position and Duties. Executive currently serves as the President and
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          Chief Executive Officer of the Company and shall have the normal
          duties, responsibilities and authority of the President and Chief
          Executive Officer, subject to the overall direction and authority of
          the Company's Board of Directors (the "Board"). All references to
          Executive's title and position in the Agreement are hereby amended to
          provide that Executive is the President and Chief Executive Officer,
          reporting to the Board.

     2.     Base Salary and Benefits.
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          (a)  Section 3(c) of the Agreement is hereby amended to read in its
          entirety as follows:

              "(c) In addition to the Base Salary for each of the Company's
              fiscal years beginning with the 2000 fiscal year, Executive will
              be eligible to earn a bonus base of up to fifty percent (50%) of
              his Base Salary (the "Bonus") based on the Company achieving
              certain corporate performance goals and Executive achieving
              certain individual goals. The target amount of the Bonus, the
              corporate performance goals and the individual goals each shall be
              set annually by the Board. The amount of the Bonus shall be
              determined in accordance with the procedures set forth on Exhibit
                                                                        -------
              B attached hereto."
              -

          (b)  All references in the Agreement to Executive's Bonus are hereby
          amended to provide that the amount of the Bonus is based on fifty
          percent (50%) of Executive's Base Salary.
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     3.     Stock Options. Section 5(a) of the Agreement provides for the grant
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         to Executive of nonstatutory options to purchase two hundred thousand
         (200,000) shares of the Company's Common Stock and further provides
         that the vesting of the options shall be accelerated and the options
         shall become immediately exercisable upon a Sale of the Company (as
                                                     -------------------
         such term is defined in Section 5(b) of the Agreement). Subsequent to
         the grant of the originally contemplated by the Agreement, Executive
         has been granted additional options to purchase shares of the Company's
         Common Stock pursuant to the Management and 2000 Equity Incentive Plan
         option agreements dated July 20, 1999 and July 28, 2000 and may be
         granted additional options to purchase shares of the Company's Common
         Stock in the future (collectively, the "Subsequent Options"). The stock
         option agreements with respect to all of the Subsequent Options shall
         provide that the vesting of the Subsequent Options shall be accelerated
         and the Subsequent Options shall become immediately exercisable upon a
         Sale of the Company (as such term is defined in Sections 5(b) of the
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         Agreement).

     4.     Remainder of Agreement. Except as expressly set forth herein, the
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         terms of the Agreement shall remain in full force and effect without
         modification or amendment.

     IN WITNESS WHEREOF, the parties hereto have executed this Amendment as of
the date first written above.


                                        Therma-Wave, Inc.


                                        By:  /s/ L. Ray Christie
                                             -------------------
                                             Name: L. Ray Christie
                                                   ---------------
                                             Title: Vice President, CFO
                                                    -------------------


                                        /s/ Martin M. Schwartz
                                        ----------------------
                                        Martin M. Schwartz