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                                                                   EXHIBIT 10.30

                                THIRD AMENDMENT
                                ---------------


          THIRD AMENDMENT (this "Amendment"), dated as of March 3, 2000, among
THERMA-WAVE, INC., a Delaware corporation (the "Borrower"), the lenders party to
the Credit Agreement referred to below (each a "Bank" and, collectively, the
"Banks") and BANKERS TRUST COMPANY, as Agent (the "Agent"). All capitalized
terms used herein and not otherwise defined herein shall have the respective
meanings provided such terms in the Credit Agreement referred to below.

                             W I T N E S S E T H:

          WHEREAS, the Borrower, the Banks and the Agent are parties to a Credit
Agreement, dated as of May 16, 1997 (as amended, modified or supplemented
through, but not including, the date hereof, the "Credit Agreement"); and

          WHEREAS, the Borrower has requested, and the Banks are willing to
grant (subject to the terms and conditions hereof), certain amendments to the
Credit Agreement as set forth herein;

          NOW, THEREFORE, it is agreed:

          1.   Section 8.06 of the Credit Agreement is hereby amended by (I)
deleting the word "and" appearing at the end of clause (iii) thereof, (ii)
deleting the period appearing at the end of clause (iv) thereof and inserting
";and" in lieu thereof and (iii) inserting the following the new clause (v) at
the end thereof:

          "(v) the Borrower may use that portion of the net cash proceeds
received by it from an initial registered public offering of Common Stock that
were not used to prepay outstanding Senior Notes as permitted by Section
8.12(ii) and/or not required to reduce the Total Revolving Loan Commitment
pursuant to Section 3.03(d) to redeem the Seller Preferred Stock in accordance
with the terms thereof so long as (I) no Default or Event of Default then exists
or would result therefrom and (ii) such net cash proceeds are so used on or
prior to April 28, 2000."

          2.   Section 8.12 of the Credit Agreement is hereby amended by
inserting the following new language immediately after the text "Section
3.03(d)" appearing in clause (ii) thereof:

          "and/or are not used to redeem Seller Preferred Stock as permitted by
          Section 8.06(v)"

          3.   In order to induce the Banks to enter into this Amendment, the
Borrower hereby represents and warrants that (i) the representations, warranties
an agreements contained in Section 6 of the Credit Agreement are true and
correct in all material respects on and as of the Third Amendment Effective Date
(as defined below), both before and after giving effect to this Amendment and
(ii) there exists no Default or Event of Default on the Third Amendment
Effective Date, both before and after giving effect to this Amendment.

          4.   This Amendment is limited as specified and shall not constitute
a modification, acceptance or waiver of any other provision of the Credit
Agreement or any other provision of any other Credit Document.

          5.   This Amendment may be executed in any number of counterparts
and by the different parties hereto on separate counterparts, each of which
counterparts when executed and delivered shall be an original, but all of which
shall together constitute one and the same instrument. A complete set of
counterparts shall be lodged with the Borrower and the Agent.

          6.   This Amendment and the rights and obligations of the parties
hereunder shall be construed in accordance with and governed by the law of the
State of New York.

          7.   This Amendment shall become effective as of the date first above
written on the date (the "Third Amendment Effective Date") when the Borrower and
the Required Banks shall have signed a counterpart hereof

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(whether the same or different counterparts) and shall have delivered (included
by way of facsimile transmission) the same to the Agent at the Notice Office.

          8.   From and after the Third Amendment Effective Date, all references
in the Credit Agreement and each of the other Credit Documents to the Credit
Agreement shall be deemed to be references to the Credit Agreement as amended
hereby.

                                     * * *

          IN WITNESS WHEREOF, each of the parties hereto has caused a
counterpart of this Amendment to be duly executed and delivered as of the date
first above written.


                                        THERMA-WAVE, INC.



                                        By:  /s/ L. RAY CHRISTIE
                                           -------------------------------------
                                        Title:  Vice President, CFO & Secretary



                                        BANKERS TRUST COMPANY
                                           Individually and as Agent

                                        By:  /s/ SUSAN L. LE FEVRE
                                           -------------------------------------
                                        Title:  Director



                                        FLEET BANK N.A.

                                        By:_____________________________________
                                        Title:

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