EXHIBIT 32.1

                  CERTIFICATION OF CHIEF EXECUTIVE OFFICER AND
                            CHIEF FINANCIAL OFFICER
            PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

     Each of the undersigned  hereby certifies,  for the purposes of Section 906
of the  Sarbanes-Oxley Act of 2002, in his capacity as an officer of Nanometrics
Incorporated (the Company"), that, to his knowledge:

   (i)   the Quarterly Report on Form 10-Q/A of the Company for the period ended
         September 30, 2003 (the "Report") fully complies with the  requirements
         of Section 13(a) or Section  15(d),  as  applicable,  of the Securities
         Exchange Act of 1934, as amended; and

   (ii)  the  information  contained  in  the  Report  fairly  presents,  in all
         material respects, the financial condition and results of operations of
         the Company.

     This written  statement is being  furnished to the  Securities and Exchange
Commission as an exhibit on Form 10-Q/A.


Date: December 12, 2003                               /s/    John D. Heaton
                                                      ---------------------
                                                      John D. Heaton
                                                      Chief Executive Officer

Date: December 12, 2003                               /s/    Paul B. Nolan
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                                                      [GRAPHIC OMITTED]
                                                      Paul B. Nolan
                                                      Chief Financial Officer