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                                                                   Exhibit 10.12

                     AMENDMENT NO. 1 TO EMPLOYMENT AGREEMENT

      AMENDMENT dated as of March 2, 2004 (this "AMENDMENT") to the Employment
Agreement dated as of November 15, 2002 (the "EMPLOYMENT AGREEMENT") by and
among Ultra Clean Technology Systems and Service, Inc., a Delaware corporation
(together with its successors, the "COMPANY"), Ultra Clean Holdings, Inc., a
Delaware corporation ("PARENT"), and Kevin Griffin ("EXECUTIVE").

      WHEREAS, the Company, Parent and Executive previously entered into the
Employment Agreement;

      WHEREAS, the Company, Parent and Executive desire to amend certain terms
of Executive's employment as set forth in this Amendment;

      NOW THEREFORE the parties hereto agree as follows:

      Section 1. Defined Terms; References. Unless otherwise specifically
defined herein, each term used herein which is defined in the Employment
Agreement has the meaning assigned to such term in the Employment Agreement.
Each reference to "hereof", "hereunder", "herein" and "hereby" and each other
similar reference and each reference to "this Agreement" and each other similar
reference contained in the Employment Agreement shall, after this Amendment
becomes effective, refer to the Employment Agreement as amended hereby

      Section 2. Amendment To Section 2.01. Executive's Base Salary from and
after the date of this Amendment shall be $150,000.

      Section 3. Amendment To Section 2.02. Section 2.02 of the Employment
Agreement is hereby amended in its entirety to read as follows:

            Section 2.02 Bonus. Executive shall be eligible to participate in an
      executive bonus plan in accordance with the terms and conditions of such
      plan, as determined by the Board in its sole discretion. For fiscal 2004,
      Executive's target bonus opportunity shall be $95,000, subject to meeting
      such performance criteria (including Company performance goals and/or
      individual performance goals) as shall be set by the Board in its
      discretion.

      Section 4. Amendment To Section 3.03. Section 3.03 of the Employment
Agreement is hereby amended by deleting Section 3.03(d) in its entirety and
re-numbering Section 3.03(e) to be Section 3.03(d).

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      Section 5. Governing Law. This Amendment shall be governed by and
construed in accordance with the laws of the State of California.

      Section 6. Counterparts. This Amendment may be executed in any number of
counterparts, each of which shall be an original but all of which together shall
constitute one instrument.

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

                                            ULTRA CLEAN TECHNOLOGY
                                            SYSTEMS AND SERVICE, INC.


                                            By:  _____________________
                                                 Name:
                                                 Title:


                                            ULTRA CLEAN HOLDINGS, INC.


                                            By:  _____________________
                                                 Name:
                                                 Title:


                                            EXECUTIVE:

                                            _________________________
                                            Kevin Griffin


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