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                                                                   Exhibit 10.35


                      SECOND AMENDMENT TO CREDIT AGREEMENT

         This SECOND AMENDMENT TO CREDIT AGREEMENT (this "Second Amendment"),
dated as of August 1, 2003, is among CABOT MICROELECTRONICS CORPORATION, a
Delaware corporation (the "Company"), the financial institutions parties to the
Credit Agreement described below, as Banks thereunder, LASALLE BANK NATIONAL
ASSOCIATION, in its capacity as Administrative Agent and Issuing Bank under such
Credit Agreement, and NATIONAL CITY BANK OF MICHIGAN/ILLINOIS, in its capacity
as Syndication Agent under such Credit Agreement.

                                 R E C I T A L S

         A. The Company, the Banks, the Administrative Agent, the Issuing Bank
and the Syndication Agent entered into a Credit Agreement dated as of July 10,
2001 (the "Original Credit Agreement"), as amended by that certain First
Amendment to Credit Agreement dated as of February 5, 2002 (the "First
Amendment") between the Company, the Banks, the Administrative Agent, the
Issuing Bank and the Syndication Agent (the Original Credit Agreement, as
amended by the First Amendment, hereinafter is referred to as the "Credit
Agreement"), pursuant and subject to the terms and conditions of which, among
other things, the Banks and the Issuing Bank agreed to make loans and other
financial accommodations to the Company.

         B. The Company has requested certain amendments to the Credit
Agreement.

         C. Subject to the terms and conditions of this Second Amendment, the
Banks, the Administrative Agent, the Issuing Bank and the Syndication Agent are
willing to agree to the requests of the Company.

         NOW, THEREFORE, in consideration of the mutual agreements contained
herein, and subject to the terms and conditions hereof, the parties hereto
hereby agree as follows:

         1. INCORPORATION OF RECITALS. The Recitals set forth above are
incorporated herein, are acknowledged by the Company to be true and correct and
are made a part hereof.

         2. DEFINITIONS. All capitalized terms used but not elsewhere defined
herein shall have the respective meanings ascribed to such terms in the Credit
Agreement, as amended by this Second Amendment.

         3. AMENDMENT TO CREDIT AGREEMENT. The Credit Agreement is amended by
deleting the definition of "Cash Equivalent Investment" set forth in Section 1.1
and substituting the following version in lieu thereof:

                  "Cash Equivalent Investment means, at any time, (a) any
         evidence of Debt, maturing not more than one year after such time,
         issued or guaranteed by the United States government or any agency
         thereof (or, in the case of foreign operations, any country that is a
         member of the Organisation for Economic Co-operation and Development),
         (b) commercial paper, maturing not more than one year from the date of
         issue, or corporate demand notes, in each case rated at least A-l by
         Standard & Poor's

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         Ratings Group ("S&P") or P-l by Moody's Investors Service, Inc.
         ("Moody's"), including asset-backed commercial paper, (c) any
         certificate of deposit (or time deposits represented by such
         certificates of deposit) or banker's acceptance, maturing not more than
         one year after such time, or overnight Federal Funds transactions that
         are issued or sold by any Bank or its holding company or by a
         commercial banking institution that is a member of the Federal Reserve
         System (or, in the case of foreign operations, a commercial banking
         institution organized under the laws of a country that is a member of
         the Organisation for Economic Co-operation and Development) and has a
         combined capital and surplus and undivided profits of not less than
         $500,000,000, (d) any repurchase agreement entered into with any Bank
         (or other commercial banking institution of the stature referred to in
         clause (c)) which (i) is secured by a fully perfected security interest
         in any obligation of the type described in any of clauses (a) through
         (c) and (ii) has a market value at the time such repurchase agreement
         is entered into of not less than 100% of the repurchase obligation of
         such Bank (or other commercial banking institution) thereunder, (e)
         asset backed securities having a short term rating of at least A-l by
         S&P or P-l by Moody's or a long term rating of at least AAA by S&P or
         Aaa by Moody's, (f) money market mutual funds rated at least AAA by S&P
         or Aaa by Moody's, (g) tax exempt variable rate commercial paper,
         tax-exempt adjustable rate option tender bonds, and other tax-exempt
         bonds or notes issued by municipalities in the United States, having a
         short term rating of MIG-1 or VMIG-1 or A-1 or a long term rating of
         AAA by S&P or Aaa by Moody's, (h) taxable and tax-exempt auction rate
         preferred stock or bonds issued with a rate reset mechanism and a
         maximum term of 49 days issued by issuers who have a rating of at least
         AAA by S&P or Aaa by Moody's, (i) liquidity vehicles including demand
         notes and funding agreements rated at least A1 by S&P or P1 by Moody's
         and (j) any other financial instrument and/or investment mechanism as
         agreed to in writing by the Company, the Banks, the Administrative
         Agent, the Issuing Bank and the Syndication Agent."

         4. CONDITIONS TO EFFECTIVENESS. The effectiveness of this Second
Amendment shall be subject to the satisfaction of all of the following
conditions in a manner, form and substance satisfactory to the Administrative
Agent:

                  (A) DELIVERY OF DOCUMENT. This Second Amendment shall have
         been executed by the Company, Syndication Agent and each Bank and shall
         have been delivered to the Administrative Agent.

                  (B) PERFORMANCE; NO DEFAULT. The Company shall have performed
         and complied with all agreements and conditions contained in the Loan
         Documents to be performed by or complied with by it, and no Event of
         Default or Unmatured Event of Default shall exist.

                  (C) MATERIAL ADVERSE EFFECT. No event shall have occurred
         since September 30, 2001 which has had or is reasonably expected to
         have a Material Adverse Effect.

         The date on which all of the conditions set forth in this Paragraph 4
have been satisfied is referred to herein as the "Effective Date."



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         5. REFERENCES. From and after the Effective Date, all terms used in the
Loan Documents which are defined in the Credit Agreement shall be deemed to
refer to such terms as amended by this Second Amendment.

         6. REPRESENTATIONS AND WARRANTIES. The Company represents and warrants
to the Banks, the Administrative Agent, the Syndication Agent and the Issuing
Bank that (i) the Company has full power and authority to execute and deliver
this Second Amendment and to perform its obligations hereunder, (ii) upon the
execution and delivery hereof, this Second Amendment will be valid, binding and
enforceable upon the Company in accordance with its terms, (iii) the execution
and delivery of this Second Amendment does not and will not contravene, conflict
with, violate or constitute a default under (A) its articles of incorporation or
by-laws or (B) any applicable law, rule, regulation, judgment, decree or order
or any agreement, indenture or instrument to which the Company is a party or is
bound or which is binding upon or applicable to all or any portion of the
Company's properties or assets and (iv) as of the date hereof no Unmatured Event
of Default or Event of Default exists.

         7. NO FURTHER AMENDMENTS; RATIFICATION OF LIABILITY. Except as amended
hereby, the Credit Agreement and each of the other Loan Documents shall remain
in full force and effect in accordance with its respective terms. The Company
hereby ratifies and confirms its liabilities, obligations and agreements under
the Credit Agreement and the other Loan Documents, all as amended by this Second
Amendment, and acknowledges that (i) it has no defenses, claims or set-offs to
the enforcement by the Banks, the Administrative Agent, the Syndication Agent or
the Issuing Bank of such liabilities, obligations and agreements, (ii) the
Banks, the Administrative Agent, the Syndication Agent and the Issuing Bank have
fully performed all obligations to the Company which they may have had or have
on and as of the date hereof and (iii) other than as specifically set forth
herein, the Banks, the Administrative Agent, the Syndication Agent and the
Issuing Bank do not waive, diminish or limit any term or condition contained in
the Credit Agreement or the other Loan Documents. The agreement of the Banks,
the Administrative Agent, the Syndication Agent and the Issuing Bank to the
terms of this Second Amendment or any other amendment of the Credit Agreement
shall not be deemed to establish or create a custom or course of dealing among
the Banks, the Administrative Agent, the Syndication Agent, the Issuing Bank and
the Company. The Loan Documents, as amended by this Second Amendment, contain
the entire agreement among the Banks, the Administrative Agent, the Syndication
Agent and the Issuing Bank with respect to the transactions contemplated hereby.

         8. COUNTERPARTS. This Second Amendment may be executed in one or more
counterparts, each of which shall be deemed an original, and all of which, when
taken together, shall constitute one and the same instrument.

         9. FURTHER ASSURANCES. The Company will at any time and from time to
time do, execute, acknowledge and deliver, or will cause to be done, executed,
acknowledged and delivered, all such further acts, documents and instruments as
reasonably may be required by the Banks, the Administrative Agent, the
Syndication Agent or the Issuing Bank in order to effectuate fully the intent of
this Second Amendment.





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         10. SEVERABILITY. If any term or provision of this Second Amendment or
the application thereof to any party or circumstance shall be held to be
invalid, illegal or unenforceable in any respect by a court of competent
jurisdiction, the validity, legality and enforceability of the remaining terms
and provisions of this Second Amendment shall not in any way be affected or
impaired thereby, and the affected term or provision shall be modified to the
minimum extent permitted by law so as most fully to achieve the intention of
this Second Amendment.

         11. CAPTIONS. The captions in this Second Amendment are inserted for
convenience of reference only and in no way define, describe or limit the scope
or intent of this Second Amendment or any of the provisions hereof.

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         IN WITNESS WHEREOF, this Second Amendment has been executed and
delivered by each of the parties hereto by a duly authorized officer of each
such party on the date first set forth above.

                              CABOT MICROELECTRONICS CORPORATION


                              By:
                                    --------------------------------------------
                                    Name:
                                    Title:


                              LASALLE BANK NATIONAL ASSOCIATION,
                              as Administrative Agent, as Issuing Bank and as a
                              Bank


                              By:
                                    --------------------------------------------
                                    Name:
                                    Title:


                              NATIONAL CITY BANK OF
                              MICHIGAN/ILLINOIS, as Syndication Agent
                              and as a Bank


                              By:
                                    --------------------------------------------
                                    Name:
                                    Title:


                              U.S. BANK NATIONAL ASSOCIATION, as a
                              Bank


                              By:
                                    --------------------------------------------
                                    Name:
                                    Title:




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