EXHIBIT 31.2

CERTIFICATION PURSUANT TO RULE 13a-14(a) OR 15d-14(a) OF THE SECURITIES EXCHANGE ACT OF1934, AS ADOPTED PURSUANT TO SECTION 302 OF THE 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 theregistrant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.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            

|Date: February 8,  2008 |  |                                       
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|                        |  | /s/ Walter A. Shephard                
|                        |  | Walter A. Shephard                    
|                        |  | Vice President, Finance,              
|                        |  | Chief Financial Officer, and Treasurer

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