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                                                        Exhibit 10.8


                  AMENDMENT TO INDEMNIFICATION AGREEMENT


     THIS AMENDMENT TO INDEMNIFICATION AGREEMENT (the "Amendment") is dated 
as of January 13, 1997, by and between TENCOR INSTRUMENTS, a California 
corporation (the "Company"), and DENNIS J. FORTINO (the "Indemnitee").

     WHEREAS, the Company and the Indemnitee have previously entered into an 
Indemnification Agreement (the "Agreement"); and

     WHEREAS, the Company and the Indemnitee desire to amend and supplement 
the Agreement, all on the terms and conditions provided herein.

     NOW, THEREFORE, the Company and the indemnitee hereby agree as follows:

     1.   SUBSECTION 2(a) - ADVANCES OF EXPENSES. The following shall be 
          added at the end of Subsection 2(a) of the Agreement:

             Any dispute concerning the advancement of expenses shall be 
             resolved by arbitration before an arbitrator selected by 
             Indemnitee and approved by the Company. If the parties cannot 
             agree on a single arbitrator, then the claim shall be heard by a 
             panel of three arbitrators, with one selected by Indemnitee, one 
             selected by the Company and one selected jointly by the 
             foregoing two arbitrators. Each of the arbitrators shall be a 
             litigation or corporate attorney with experience in the field of 
             officer and director indemnification. The arbitrators shall be 
             selected within fifteen (15) days after demand for arbitration 
             and shall render a decision within forty-five (45) days after 
             selection, unless good cause is shown for requiring a longer 
             decision period. The Company shall act in utmost good faith to 
             provide timely information to the arbitrators and insure 
             Indemnitee a full opportunity to defend against the Company's 
             claim that Indemnitee is not entitled to an advance of expenses. 
             The Company shall indemnify Indemnity against all expenses 
             incurred by Indemnitee under the dispute resolutions proceedings
             set forth in this Subsection 2(a), unless a court of competent 
             jurisdiction finds that each of the claims and/or defenses by 
             indemnitee in the action or proceeding for which an advance is 
             sought was frivolous or made in bad faith.

     2.   SUBSECTION 2(c) - PROCEDURE. The third sentence of Subsection 2(c) 
          of the agreement shall be amended in its entirety to read as 
          follows:

             It shall be a defense to any such action (other than an action 
             brought to enforce a claim for expenses incurred in connection 
             with any action or proceeding in advance of its final 
             disposition) that Indemnitee has not met the standards of 
             conduct which make it permissible under applicable law for the 
             Company to indemnify Indemnitee for the amount claimed, but it 
             shall be presumed that Indemnitee has met any applicable 
             standard of conduct required for indemnification, unless the 
             Company has affirmatively shown that Indemnitee did not meet 
             that standard, and Indemnitee shall be entitled to receive 
             interim payments of expenses pursuant to Subsection 2(a), unless 
             and until such defense may be finally adjudicated by court order 
             or judgment from which no further right of appeal exists.


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     3.   SUBSECTION 2(d) - NOTICE TO INSURERS. The following shall be 
          added at the end of Subsection 2(d) of the Agreement:

             The Company shall indemnify Indemnitee against any reasonable 
             direct or indirect costs (including, without limitation, 
             attorneys' fees and disbursements) incurred by Indemnitee in 
             connection with any successful action brought by Indemnitee for 
             recovery under any insurance policies referred to in this 
             Subsection 2(d) and shall advance to Indemnitee the costs of 
             such action in the manner provided in Subsection 2(a) hereof.

     4.   NO FURTHER AMENDMENT. Except as specifically provided herein, the 
          Agreement shall not be amended and shall remain in full force 
          and effect.

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

                                      COMPANY:
                                      TENCOR INSTRUMENTS


                                      By: _______________________________
                                          Its:

                                      INDEMNITEE: