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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0000950117-05-000652.txt : 20050217
<SEC-HEADER>0000950117-05-000652.hdr.sgml : 20050217
<ACCEPTANCE-DATETIME>20050217145913
ACCESSION NUMBER:		0000950117-05-000652
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050216
FILED AS OF DATE:		20050217
DATE AS OF CHANGE:		20050217

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ZYGO CORP
		CENTRAL INDEX KEY:			0000730716
		STANDARD INDUSTRIAL CLASSIFICATION:	OPTICAL INSTRUMENTS & LENSES [3827]
		IRS NUMBER:				060864500
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		LAUREL BROOK RD
		CITY:			MIDDLEFIELD
		STATE:			CT
		ZIP:			06455
		BUSINESS PHONE:		8603478506

	MAIL ADDRESS:	
		STREET 1:		LAUREL BROOK ROAD
		CITY:			MIDDLEFIELD
		STATE:			CT
		ZIP:			06455

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SHEPHARD WALTER A
		CENTRAL INDEX KEY:			0001282381

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-12944
		FILM NUMBER:		05623857

	BUSINESS ADDRESS:	
		STREET 1:		ZYGO CORP
		STREET 2:		LAUREL BROOK ROAD
		CITY:			MIDDLEFIELD
		STATE:			CO
		ZIP:			06455
		BUSINESS PHONE:		8603478506

	MAIL ADDRESS:	
		STREET 1:		ZYGO CORP
		STREET 2:		LAUREL BROOK ROAD
		CITY:			MIDDLEFIELD
		STATE:			CT
		ZIP:			06455
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>rsr_11273.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-02-16</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000730716</issuerCik>
        <issuerName>ZYGO CORP</issuerName>
        <issuerTradingSymbol>ZIGO</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001282381</rptOwnerCik>
            <rptOwnerName>SHEPHARD WALTER A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ZYGO CORPORATION, LAUREL BROOK ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MIDDLEFIELD</rptOwnerCity>
            <rptOwnerState>CT</rptOwnerState>
            <rptOwnerZipCode>06455</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Financial  Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-02-16</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>12.95</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>968</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Includes 468 shares in January 2005 purchased through the Zygo Corporation Employee Stock Purchase Plan.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Walter A Shephard</signatureName>
        <signatureDate>2005-02-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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