EXHIBIT 99.1

                                                                  EXECUTION COPY

                  AMENDED AND RESTATED SHAREHOLDER AGREEMENT

          THIS AMENDED AND RESTATED SHAREHOLDER AGREEMENT (this "Agreement") is
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effective as of May 16, 2001 and is entered into on June 4, 2001, by and among
Credence Systems Corporation, a Delaware corporation ("Parent"), Iguana
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Acquisition Corporation, an Oregon corporation and wholly owned subsidiary of
Parent ("Merger Sub"), and the undersigned shareholder ("Shareholder") of
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Integrated Measurement Systems, Inc., a Oregon corporation ("Company").
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                                   RECITALS:

          WHEREAS, Parent has agreed to acquire the outstanding securities of
Company pursuant to a statutory merger of Merger Sub with and into Company (the
"Merger") effected in part through the conversion of each outstanding share of
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capital stock of Company (the "Company Capital Stock"), into shares of common
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stock of Parent (the "Parent Shares") at the rate set forth in the Agreement and
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Plan of Merger and Reorganization dated as of May 16, 2001 by and among Parent,
Merger Sub and Company (such agreement as it may be amended or restated is
hereinafter referred to as the "Reorganization Agreement") (the "Transaction");
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          WHEREAS, Shareholder is the registered and beneficial owner of such
number of shares of the outstanding Company Capital Stock as is indicated on the
signature page of this Agreement (the "Shares");
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          WHEREAS, in order to induce Parent to enter into the Transaction,
certain shareholders of Company have agreed to vote the Shares and any other
such shares of Company Capital Stock so as to facilitate consummation of the
Transaction;

          WHEREAS, concurrent with the execution of the Reorganization
Agreement, Parent, Merger Sub and Shareholder entered into the Shareholder
Agreement, dated as of May 16, 2001 (the "Prior Agreement"); and
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          WHEREAS, Parent, Merger Sub and Shareholder desire to amend and
restate the Prior Agreement and have agreed that (a) the Prior Agreement be of
no further force and effect and (b) this Agreement supercedes and replaces the
Prior Agreement in its entirety.

          NOW, THEREFORE, in consideration of the promises and mutual
agreements, provisions and covenants set forth in the Reorganization Agreement,
the parties hereto agree as follows:

          1.   Share Ownership and Agreement to Retain Shares.
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               1.1  Encumbrance. Shareholder represents, warrants and, in
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subclause (v) below, covenants to Parent that (i) Shareholder is the beneficial
owner of that number of Shares of Company Capital Stock set forth on the
signature page hereto; (ii) except as otherwise set forth on the signature page
hereto, Shareholder has held such Company Capital Stock at all


times since the date set forth on such signature page; (iii) the Shares
constitute the Shareholder's entire equity interest in the outstanding Company
Capital Stock; (iv) no other person or entity not a signatory to this Agreement
has a beneficial interest in or a right to acquire the Shares or any portion of
the Shares; and (v) the Shares are and will be at all times up until the
Expiration Date free and clear of any liens, claims, rights of first refusal,
options, charges or other encumbrances. For the avoidance of doubt, nothing in
this Agreement shall deem shares of outstanding Company Capital Stock or options
to acquire Company Capital Stock held by an officer, director or employee of
Shareholder to be beneficially owned by Shareholder. As used herein, the term
"Expiration Date" shall mean the earlier to occur of (A) the Effective Time (as
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defined in the Reorganization Agreement) of the Transaction, and (B) the
termination of the Reorganization Agreement pursuant to its terms.

               1.2  New Shares. Shareholder agrees that any shares of Company
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Capital Stock that Shareholder purchases or with respect to which Shareholder
otherwise acquires beneficial ownership after the date of this Agreement and
prior to the Expiration Date ("New Shares") shall be subject to the terms and
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conditions of this Agreement to the same extent as if they constituted Shares.

          2.   Agreement to Vote Shares. Prior to the Expiration Date, at every
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meeting of the shareholders of Company called with respect to any of the
following, and at every adjournment thereof, and on every action or approval by
written resolution of the shareholders of Company with respect to any of the
following, Shareholder shall vote the Shares and any New Shares in favor of
approval of the Transaction and any matter or actions required to facilitate the
Transaction.

          3.   Irrevocable Proxy. Shareholder is hereby delivering to Parent a
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duly executed proxy in the form attached hereto as Exhibit A (the "Proxy") with
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respect to each meeting of shareholders of Company, such Proxy to cover the
total number of Shares and New Shares in respect of which Shareholder is
entitled to vote at any such meeting. Upon the execution of this Agreement by
the Shareholder, the Shareholder hereby revokes any and all prior proxies given
by the Shareholder with respect to the Shares and agrees not to grant any
subsequent proxies with respect to the Shares or any New Shares until after the
Expiration Date.

          4.   Representations, Warranties and Covenants of Shareholder.
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Shareholder hereby represents, warrants and/or covenants to Parent as follows:

                    (a)  Until the Expiration Date, the Shareholder will not
(and will use such Shareholder's commercially reasonable efforts to cause the
Company, its affiliates, officers, directors and employees and any investment
banker, attorney, accountant or other agent retained by such Shareholder, not
to): (i) initiate or solicit, directly or indirectly, any proposal, plan of
offer to acquire all or any substantial part of the business or properties or
Company Capital Stock, whether by merger, purchase of assets, tender offer or
otherwise, or to liquidate Company or otherwise distribute to the Shareholders
of Company all or any substantial part of the business, properties or Company
Capital Stock (each, an "Acquisition Proposal"); (ii) initiate, directly or
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indirectly, any contact with any person in an effort to or with a view towards
soliciting any Acquisition Proposal; (iii) furnish information concerning
Company's business, properties or assets to any corporation, partnership,
limited liability company, limited

                                       2


partnership, person or other entity or group (other than Parent or Merger Sub,
or any associate, agent or representative of Parent or Merger Sub), under any
circumstances that would reasonably be expected to relate to an actual or
potential Acquisition Proposal; or (iv) negotiate or enter into discussions or
an agreement, directly or indirectly, with any entity or group with respect of
any potential Acquisition Proposal provided that, in the case of clauses (iii)
and (iv), the foregoing shall not prevent Shareholder, in Shareholder's capacity
as a director or officer (as the case may be) of Company, from taking any
actions permitted under Section 4.3 of the Reorganization Agreement. In the
event the Shareholder shall receive or become aware of any Acquisition Proposal
subsequent to the date hereof, such Shareholder shall promptly inform Parent as
to any such matter and the details thereof to the extent possible without
breaching any other agreement to which such Shareholder is a party or violating
its fiduciary duties.

                    (b)  Shareholder is competent to execute and deliver this
Agreement, to perform its obligations hereunder and to consummate the
transactions contemplated hereby. This Agreement has been duly and validly
executed and delivered by Shareholder and, assuming the due authorization,
execution and delivery by Parent and Merger Sub, constitutes a legal, valid and
binding obligation of Shareholder, enforceable against Shareholder in accordance
with its terms except that (i) the enforceability thereof may be subject to
applicable bankruptcy, insolvency or other similar laws, now or hereinafter in
effect affecting creditors' rights generally and (ii) the availability of the
remedy of specific performance or injunctive or other forms of equitable relief
may be subject to equitable defenses and would be subject to the discretion of
the court before which any proceeding therefor may be brought.

                    (c) The execution and delivery of this Agreement by
Shareholder does not, and the performance of this Agreement by Shareholder shall
not, result in any breach of or constitute a default (or an event that with
notice or lapse of time or both would become a default) under, or give to others
any rights of termination, amendment, acceleration or cancellation of, or result
in the creation of a lien or encumbrance, on any of the Shares or New Shares
pursuant to, any note, bond, mortgage, indenture, contract, agreement,
commitment, lease, license, permit, franchise or other instrument or obligation
to which Shareholder is a party or by which Shareholder or the Shares or New
Shares are or will be bound or affected.

          5.   Additional Documents. Shareholder hereby covenants and agrees to
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execute and deliver any additional documents necessary, in the reasonable
opinion of Parent, to carry out the purpose and intent of this Agreement.

          6.   [Reserved].
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          7.   Termination. This Agreement and the Proxy delivered in connection
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herewith shall terminate and shall have no further force or effect as of the
Expiration Date.

          8.   Confidentiality. Shareholder agrees (i) to hold any information
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regarding this Agreement and the Transaction in strict confidence, and (ii) not
to divulge any such information to any third person not subject to
confidentiality obligations, until such time as the Transaction has been
publicly disclosed by Parent, except as may otherwise be required by law.

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          9.   Miscellaneous.
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               9.1  Severability. If any term, provision, covenant or
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restriction of this Agreement or the Proxy is held by a court of competent
jurisdiction to be invalid, void or unenforceable, then the remainder of the
terms, provisions, covenants and restrictions of this Agreement shall remain in
full force and effect and shall in no way be affected, impaired or invalidated.

               9.2  Binding Effect and Assignment. This Agreement and all of the
                    -----------------------------
provisions hereof shall be binding upon and inure to the benefit of the parties
hereto and their respective successors and permitted assigns, but, except as
otherwise specifically provided herein, neither this Agreement nor any of the
rights, interests or obligations of the parties hereto may be assigned by either
of the parties hereto without the prior written consent of the other. This
Agreement is binding upon Shareholder in Shareholder's capacity as a shareholder
of Company (and not in Shareholder's capacity as a director or officer, as the
case may be, of Company) and only with respect to the specific matters set forth
herein.

               9.3  Amendment and Modification. This Agreement may not be
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modified, amended, altered or supplemented except by the execution and delivery
of a written agreement executed by the parties hereto.

               9.4  Specific Performance; Injunctive Relief. The parties hereto
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acknowledge that Parent will be irreparably harmed and that there will be no
adequate remedy at law for a violation of any of the covenants or agreements of
Shareholder set forth herein. Therefore, it is agreed that, in addition to any
other remedies that may be available to Parent or Merger Sub upon any such
violation, Parent and Merger Sub shall have the right to seek to enforce such
covenants and agreements by specific performance, injunctive relief or by any
other means available to Parent or Merger Sub at law or in equity, in connection
with such enforcement and waives any requirement for the security or posting of
any bond in connection with such enforcement.

               9.5  Notices. All notices, requests, demands or other
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communications that are required or may be given pursuant to the terms of this
Agreement shall be in writing and shall be deemed to have been duly given if
delivered by hand or mailed by registered or certified mail, postage prepaid, as
follows:

                    (a)  If to the Shareholder, at the address set forth below
the Shareholder's signature at the end hereof.

                    (b)  if to Parent or Merger Sub, to:

                    Credence Systems Corporation
                    215 Fourier Avenue
                    Fremont, California 94539
                    Attention: General Counsel
                    Telephone: (510) 657-7400
                    Facsimile: (510) 623-2591

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                    with a copy to:

                    Brobeck, Phleger & Harrison LLP
                    Two Embarcadero Place
                    2200 Geng Road
                    Palo Alto, California  94303
                    Attention:  Warren T. Lazarow, Esq.
                    Facsimile No.: (650) 496-2885
                    Telephone No.:   (650) 496-2887

                    (c)  if to Shareholder, to its address set forth on the
                         signature page

                    with a copy to:

                    Gibson, Dunn & Crutcher LLP
                    One Montgomery Street
                    Telesis Tower
                    San Francisco, California 94104
                    Attention: Gregory J. Conklin, Esq.
                    Facsimile No.: (415) 986-5309
                    Telephone No.: (415) 393-8263

or to such other address as any party hereto may designate for itself by notice
given as herein provided.

               9.6  Governing Law. This Agreement shall be governed by,
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construed and enforced in accordance with the laws of the State of Oregon
without regard to any applicable conflicts of laws rules.

               9.7  Entire Agreement. This Agreement and the Proxy contain the
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entire understanding of the parties hereto in respect of the subject matter
hereof, and supersede all prior negotiations and understandings among the
parties hereto with respect to such subject matter.

               9.8  Counterpart. This Agreement may be executed in several
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counterparts, each of which shall be an original, but all of which together
shall constitute one the same agreement.

               9.9  Effect of Headings. The section headings herein are for
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convenience only and shall not affect the construction or interpretation of this
Agreement.

               9.10 Amendment and Restatement of Prior Agreement. Parent,
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MergerSub and Shareholder hereby agree that the Prior Agreement is hereby
amended and restated by this Agreement, which supercedes and replaces the Prior
Agreement in its entirety.

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          IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
be executed as of the date first above written.


CREDENCE SYSTEMS CORPORATION            CADENCE DESIGN SYSTEMS, INC.

By: /s/ John R. Detwiler                By: /s/ R.L. Smith McKeithen
   -------------------------               -----------------------------


Name:  John R. Detwiler                 Name:  R.L. Smith McKeithen
     -----------------------                 ---------------------------
Title: Senior V.P. and CFO              Title: Sr. Vice President &
     -----------------------                    General Counsel
                                             --------------------------
                                        Address:  2655 Seely Avenue, Building 5
                                                  San Jose, California 95134
                                                  Attention: General Counsel
                                                  Facsimile No.: (408) 944-6855
                                                  Telephone No.: (408) 944-7748


IGUANA ACQUISITION CORPORATION

By: /s/ John R. Detwiler
   -------------------------

Name:  John R. Detwiler
     -----------------------
Title: CFO
      ----------------------


Total Number of Shares of Company Capital Stock owned on the date hereof:

Common Stock:                 2,559,000


                    [SIGNATURE PAGE TO AMENDED AND RESTATED
                            SHAREHOLDER AGREEMENT]


                                                                       Exhibit A
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                               IRREVOCABLE PROXY

                               TO VOTE STOCK OF

                     INTEGRATED MEASUREMENT SYSTEMS, INC.


          The undersigned shareholder of Integrated Measurement Systems, Inc., a
Oregon corporation ("Company"), hereby irrevocably (to the full extent permitted
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by the Oregon Business Corporation Act) appoints the members of the Board of
Directors of Credence Systems Corporation, a Delaware corporation ("Parent"),
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and each of them, or any other designee of Parent, as the sole and exclusive
attorneys and proxies of the undersigned, with full power of substitution and
resubstitution, to vote and exercise all voting and related rights (to the full
extent that the undersigned is entitled to do so) with respect to all of the
shares of capital stock of Company that now are or hereafter may be beneficially
owned by the undersigned, and any and all other shares or securities of Company
issued or issuable in respect thereof on or after the date hereof (collectively,
the "Shares") in accordance with the terms of this Irrevocable Proxy.  The
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Shares beneficially owned by the undersigned shareholder of Company as of the
date of this Irrevocable Proxy are listed on the final page of this Irrevocable
Proxy.  Upon the undersigned's execution of this Irrevocable Proxy, any and all
prior proxies given by the undersigned with respect to any Shares are hereby
revoked and the undersigned agrees not to grant any subsequent proxies with
respect to the Shares until after the Expiration Date (as defined below).

          This Irrevocable Proxy is irrevocable (to the extent provided in the
Oregon Business Corporation Act), is coupled with an interest, including, but
not limited to, that certain Amended and Restated Shareholder Agreement
effective as of May 16, 2001 and dated May 30, 2001, by and among Parent, Iguana
Acquisition Corporation ("Merger Sub") and the undersigned, and is granted in
                          ----------
consideration of Parent's entering into that certain Agreement and Plan of
Merger and Reorganization by and among Company, Parent and Merger Sub (the
"Reorganization Agreement"), which agreement provides for the merger of Merger
- -------------------------
Sub with and into Company (the "Merger").  As used herein, the term "Expiration
                                ------                               ----------
Date" shall mean the earlier to occur of (i) such date and time as the Merger
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shall become effective in accordance with the terms and provisions of the
Reorganization Agreement, and (ii) the date of termination of the Reorganization
Agreement pursuant to its terms.  This Irrevocable Proxy shall terminate on the
Expiration Date.

          The attorneys and proxies named above, and each of them are hereby
authorized and empowered by the undersigned, at any time prior to the Expiration
Date, to act as the undersigned's attorney and proxy to vote the Shares, and to
exercise all voting and other rights of the undersigned with respect to the
Shares (including, without limitation, the power to execute and deliver written
consents pursuant to the Oregon Business Corporation Act), at every annual,
special or adjourned meeting of the shareholders of Company and in every written
consent in lieu of such meeting as follows:


          [X]  In favor of approval of the Merger and the Reorganization
               Agreement, in favor of any matter or actions required to
               facilitate the Merger and against any proposal for any
               recapitalization, merger, sale of assets or other business
               combination relating to the Company (other than the Merger).

          The attorneys and proxies named above may not exercise this
Irrevocable Proxy on any other matter except as provided above. The undersigned
shareholder may vote the Shares on all other matters.

          All authority herein conferred shall survive the death or incapacity
of the undersigned and any obligation of the undersigned hereunder shall be
binding upon the heirs, personal representatives, successors and assigns of the
undersigned.

          This Irrevocable Proxy is coupled with an interest as aforesaid and is
irrevocable.


Dated:  May 16, 2001               CADENCE DESIGN SYSTEMS, INC.


                                   By: /s/ R.L. Smith McKeithen
                                      ---------------------------

                                   Name:  R.L. Smith McKeithen
                                   Title: Sr. Vice President & General Counsel

                                   Shares beneficially owned:
                                   2,559,000 shares of Company Common Stock