Exhibit 10.2

AMENDMENT TO LOAN DOCUMENTS

        THIS AMENDMENT TO LOAN DOCUMENTS ("this Amendment"), made and entered
into effective as of the 17th day of September, 2001, by and between JACKSON
NATIONAL LIFE INSURANCE COMPANY, a Michigan corporation ("Lender"), and APPLIED
EPI, INC., a Minnesota corporation ("Borrower").

        WITNESSETH THAT:

        WHEREAS, Lender and Borrower are parties to that certain Loan Agreement
(the "Loan Agreement") dated December 15, 1999, with respect to a loan in the
amount of $4,500,000 made by Lender to Borrower; and

        WHEREAS, Lender and Borrower desire to amend the Loan Agreement and the
other Loan Documents (as defined in the Loan Agreement) in certain respects, all
as more particularly hereinafter set forth;

        NOW, THEREFORE, in consideration of the foregoing and of the mutual
covenants and agreements contained herein and other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged,
Lender and Borrower hereby covenant and agree as follows:

1.Capitalized Terms.    Any capitalized term used herein and not otherwise
defined herein shall have the meaning ascribed to such term in the Loan
Agreement.

2.Amendments to Loan Agreement.    The Loan Agreement shall be and hereby is
amended as follows:

(a)Without limiting the generality of the definition of "Environmental Indemnity
Agreement" contained in the Loan Agreement, Borrower and Lender hereby agree
that such term shall include, without limitation, (i) that certain Environmental
Indemnity Agreement dated December 15, 1999, executed by Borrower and Chorus
International Corporation, EPI Europe, Ltd., Paul E. Colombo, Frank C. Kraemer
and David G. Reamer in favor of Lender (the liability thereunder of all such
parties other than Borrower having been released by instrument effective as of
September 17, 2001); and (ii) that certain Environmental Indemnity Agreement
dated as of September 17, 2001, executed by Veeco Instruments Inc. in favor of
Lender.

(b)Without limiting the generality of the definition of "Guaranty" contained in
the Loan Agreement, Borrower and Lender hereby agree that such term shall
include, without limitation, (i) that certain Guaranty dated December 15, 1999,
executed by Chorus International Corporation, EPI Europe, Ltd., Paul E. Colombo,
Frank C. Kraemer and David G. Reamer in favor of the Lender (the liability
thereunder of all such parties having been released by instrument effective as
of September 17, 2001); and (ii) that certain Guaranty dated as of September 17,
2001, executed by Veeco Instruments Inc. in favor of Lender.

(c)Without limiting the generality of the definition of "Indemnification
Agreement" contained in the Loan Agreement, Borrower and Lender hereby agree
that such term shall include, without limitation, (i) that certain
Indemnification Agreement dated December 15, 1999, executed by Chorus
International Corporation, EPI Europe, Ltd., Paul E. Colombo, Frank C. Kraemer
and David G. Reamer in favor of the Lender (the liability thereunder of all such
parties having been released by instrument effective as September 17, 2001); and
(ii) that certain Indemnification Agreement dated as of September 17, 2001,
executed by Veeco Instruments Inc. in favor of Lender.

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(d)The definition of "Indemnitor" contained in the Loan Agreement shall be and
hereby is amended to read in its entirety as follows:

        "Indemnitor: Veeco Instruments Inc., a Delaware corporation."

(e)So long as the financial condition and performance of Borrower is reported on
a consolidated basis with Indemnitor, the requirements of Section 3.13 of the
Loan Agreement with respect to financial statements of Borrower shall be deemed
met if financial statements of Indemnitor meeting the requirements of said
Section 3.13 with respect to financial statements of Borrower are provided at
the times that financial statements of Borrower are required to be provided
under said Section 3.13.

3.Amendments to Other Loan Documents.    All references to the "Loan Agreement"
contained in the Note, the Mortgage and the other Loan Documents shall mean and
refer to the Loan Agreement, as amended hereby, and as the same may be hereafter
supplemented or amended from time to time in writing.

4.Ratification and Confirmation.    Except as specifically amended and modified
herein, the Loan Agreement and the other Loan Documents shall be and remain in
full force and effect, and are hereby ratified and confirmed in all respects.

5.Consents.    If and to the extent required by the Loan Documents, Lender
hereby consents to (i) the merger of Borrower with and into a wholly-owned
subsidiary of Veeco Instruments Inc. and the transactions contemplated thereby;
(ii) the dissolution of Applied Epi International, Inc. (f/k/a Chorus
International Corporation), and the dissolution of Applied Epi Europe, Inc.
(f/k/a Epi Europe, Ltd.), or the combination of Applied Epi Europe, Inc. with
Borrower or affiliates of Borrower (whether by merger, sale of assets or
otherwise); and (iii) the payment, on or about September 17, 2001, by Borrower
to certain of its officers and shareholders of subordinated debt in the amount
of $5,000,000.00.

6.Counterparts.    This Amendment may be executed simultaneously in two or more
counterparts each of which shall be deemed an original, but all of which shall
constitute one and the same Amendment.

        IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed as of the day and year first above written.

    JACKSON NATIONAL LIFE INSURANCE COMPANY
 
 
PPM Finance, Inc., its Agent
 
 
By:
 
/s/  AUTHORIZED SIGNATORY      

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Its: Authorized Signatory
 
 
APPLIED EPI, INC.
 
 
By:
 
/s/  AUTHORIZED SIGNATORY      

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Its: Authorized Signatory

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