**EXHIBIT 31.2**

**CERTIFICATION PURSUANT TO RULE 13a-14(a) OR 15d-14(a)OF THE SECURITIES EXCHANGE ACT OF 1934,AS ADOPTED PURSUANT TO SECTION 302 OFTHE SARBANES-OXLEY ACT OF 2002**

I, Walter A. Shephard, certify that:

| 1)                                               | I        have reviewed this quarterly****report    on Form 10-Q of Zygo Corporation;                                                                                                                                                                                                                                                                                 |
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| 2)                                               | Based on my knowledge, this report does not        contain any untrue statement of a material fact or omit to state a material        fact necessary to make the statements made, in light of the circumstances        under which such statements were made, not misleading with respect to    the period covered by this report;                                   |
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| 3)                                     | Based on my knowledge, the financial statements,        and other financial information included in this report, fairly present        in all material respects the financial condition, results of operations        and cash flows of the registrant as of, and for, the periods presented    in this report;                                                      |
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| 4)                                     | The registrant’s other certifying officer(s)        and I are responsible for establishing and maintaining disclosure controls        and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e))        and internal control over financial reporting (as defined in Exchange    Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have: |
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|                                             |                                                                                                                                                                                                                                                                                                                              | a)      Designed such disclosure controls and procedures, or caused such          disclosure controls and procedures to be designed under our supervision,          to ensure that material information relating to the registrant, including          its consolidated subsidiaries, is made known to us by others within          those entities, particularly during the period in which this report          is being prepared; 

b)     Designed          such internal control over financial reporting, or caused such internal          control over financial reporting to be designed under our supervision,          to provide reasonable assurance regarding the reliability of financial          reporting and the preparation of financial statements for external          purposes in accordance with generally accepted accounting principles; 

c)      Evaluated          the effectiveness of the registrant’s disclosure controls and          procedures and presented in this report our conclusions about the effectiveness          of the disclosure controls and procedures, as of the end of the period          covered by this report based on such evaluation; and 

d)      Disclosed in this report any change in the registrant’s internal          control over financial reporting that occurred during the registrant’s          most recent fiscal quarter (the registrant’s fourth fiscal quarter          in the case of an annual report) that has materially affected, or is          reasonably likely to materially affect, the registrant’s internal    control over financial reporting; and |
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| 5)                                     | The registrant’s other certifying        officer(s) and I have disclosed, based on our most recent evaluation        of internal control over financial reporting, to the registrant’s        auditors and the audit committee of the registrant’s board of directors (or persons performing the    equivalent functions):                            |
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|                                             |                                                                                                                                                                                                                                                                                                                                                                 | a)      All          significant deficiencies and material weaknesses in the design or operation          of internal control over financial reporting which are reasonably likely          to adversely affect the registrant’s ability to record, process,          summarize and report financial information; and 

b)     Any          fraud, whether or not material, that involves management or other employees          who have a significant role in the registrant’s internal control    over financial reporting. |