Exhibit 99.1


      CERTIFICATION OF CHIEF EXECUTIVE OFFICER AND CHIEF FINANCIAL OFFICER
                                   PURSUANT TO
                             18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

I, John D.  Heaton,  certify,  pursuant to 18 U.S.C.  Section  1350,  as adopted
pursuant to Section 906 of the  Sarbanes-Oxley  Act of 2002,  that the Quarterly
Report of Nanometrics  Incorporated on Form 10-Q for the quarterly  period ended
March 31, 2003 fully complies with the requirements of Section 13(a) or 15(d) of
the  Securities  Exchange  Act of 1934 and that  information  contained  in such
Quarterly  Report on Form 10-Q fairly  presents  in all  material  respects  the
financial condition and results of operations of Nanometrics Incorporated.



                            By: /s/ John D. Heaton
                               ---------------------------------
                            Name:      John D. Heaton
                            Title:     Chief Executive Officer



I, Paul B.  Nolan,  certify,  pursuant  to 18 U.S.C.  Section  1350,  as adopted
pursuant to Section 906 of the  Sarbanes-Oxley  Act of 2002,  that the Quarterly
Report of Nanometrics  Incorporated on Form 10-Q for the quarterly  period ended
March 31, 2003 fully complies with the requirements of Section 13(a) or 15(d) of
the  Securities  Exchange  Act of 1934 and that  information  contained  in such
Quarterly  Report on Form 10-Q fairly  presents  in all  material  respects  the
financial condition and results of operations of Nanometrics Incorporated.



                             By: /s/ Paul B. Nolan
                                --------------------------
                             Name:      Paul B. Nolan
                             Title:     Chief Financial Officer




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