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                                                                    EXHIBIT 32.1

      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, J. Bruce Robinson, certify, pursuant to 18 U.S.C. Section 1350, as
adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that the
Annual Report of Zygo Corporation on Form 10-K for the fiscal year ended June
30, 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 Annual
Report on Form 10-K fairly presents, in all material respects, the financial
condition and results of operations of Zygo Corporation.

    A signed original of this written statement required by Section 906 has been
provided to Zygo Corporation and will be retained by Zygo Corporation and
furnished to the Securities and Exchange Commission or its staff upon request.

                                          By:     /s/ J. BRUCE ROBINSON
                                          Name:   J. Bruce Robinson
                                          Title:  Chairman, President and Chief
                                                  Executive Officer

    I, Richard M. Dressler, certify, pursuant to 18 U.S.C. Section 1350, as
adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that the
Annual Report of Zygo Corporation on Form 10-K for the fiscal year ended June
30, 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 Annual
Report on Form 10-K fairly presents, in all material respects, the financial
condition and results of operations of Zygo Corporation.

    A signed original of this written statement required by Section 906 has been
provided to Zygo Corporation and will be retained by Zygo Corporation and
furnished to the Securities and Exchange Commission or its staff upon request.

                                          By:     /s/ RICHARD M. DRESSLER
                                          Name:   Richard M. Dressler
                                          Title:  Vice President, Finance,
                                                  Chief Financial Officer, and
                                                  Treasurer