AMENDED AND RESTATED
 
                          CERTIFICATE OF INCORPORATION
 
                                       OF
 
                           ULTRA CLEAN HOLDINGS, INC.
 
                                    * * * * *
 
         FIRST: The name of the Corporation is Ultra Clean Holdings, Inc.
 
         SECOND: The address of its registered office in the State of Delaware
is 15 East North Street, Dover, County of Kent, Delaware 19901. The name of its
registered agent at such address is Incorporating Services, Ltd.
 
         THIRD: The purpose of the Corporation is to engage in any lawful act or
activity for which corporations may be organized under the General Corporation
Law of the State of Delaware as the same exists or may hereafter be amended
("DELAWARE LAW").
 
         FOURTH: The total number of shares of stock which the Corporation shall
have authority to issue is 100,000,000, consisting of 90,000,000 shares of
Common Stock, par value $0.001 per share (the "COMMON STOCK"), and 10,000,000
shares of Preferred Stock, par value $0.001 per share (the "PREFERRED STOCK").
 
         Each share of Common Stock, either issued and outstanding or held by
the Corporation as treasury stock immediately prior to the time this Amended and
Restated Certificate of Incorporation becomes effective shall be and is hereby
automatically reclassified and changed into a 1/4 (one-fourth) fully-paid and
non-assessable share of Common Stock without increasing or decreasing the par
value of each share of Common Stock; provided that no fractional shares shall be
issued.
 
         The Board of Directors is hereby empowered to authorize by resolution
or resolutions from time to time the issuance of one or more classes or series
of Preferred Stock and to fix the designations, powers, preferences and
relative, participating, optional or other rights, if any, and the
qualifications, limitations or restrictions thereof, if any, with respect to
each such class or series of Preferred Stock and the number of shares
constituting each such class or series, and to increase or decrease the number
of shares of any such class or series to the extent permitted by the General
Corporation Law of the State of Delaware, as amended from time to time.
 
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         FIFTH: Each holder of Common Stock, as such, shall be entitled to one
vote for each share of Common Stock held of record by such holder on all matters
on which stockholders generally are entitled to vote; provided, however, that,
except as otherwise required by law, holders of Common Stock, as such, shall not
be entitled to vote on any amendment to this Certificate of Incorporation
(including any Certificate of Designations relating to any series of Preferred
Stock) that relates solely to the terms of one or more outstanding series of
Preferred Stock if the holders of such affected series are entitled, either
separately or together with the holders of one or more other such series, to
vote thereon pursuant to this Certificate of Incorporation (including any
Certificate of Designations relating to any series of Preferred Stock) or
pursuant to Delaware Law.
 
         SIXTH: The Board of Directors shall have the power to adopt, amend or
repeal the bylaws of the Corporation.
 
         SEVENTH: Election of directors need not be by written ballot unless the
bylaws of the Corporation so provide.
 
         EIGHTH: (1) A director of the Corporation shall not be liable to the
Corporation or its stockholders for monetary damages for breach of fiduciary
duty as a director to the fullest extent permitted by Delaware Law.
 
     (2)(a) Each person (and the heirs, executors or administrators of such
person) who was or is a party or is threatened to be made a party to, or is
involved in any threatened, pending or completed action, suit or proceeding,
whether civil, criminal, administrative or investigative, by reason of the fact
that such person is or was a director or officer of the Corporation or is or was
serving at the request of the Corporation as a director or officer of another
corporation, partnership, joint venture, trust, employee benefit plan or other
enterprise, shall be indemnified and held harmless by the Corporation to the
fullest extent permitted by Delaware Law. The right to indemnification conferred
in this ARTICLE EIGHTH shall also include the right to be paid by the
Corporation the expenses incurred in connection with any such proceeding in
advance of its final disposition to the fullest extent authorized by Delaware
Law. The right to indemnification conferred in this ARTICLE EIGHTH shall be a
contract right.
 
         (b) The Corporation may, by action of its Board of Directors, provide
indemnification to such of the employees and agents of the Corporation to such
extent and to such effect as the Board of Directors shall determine to be
appropriate and authorized by Delaware Law.
 
         (3) The Corporation shall have power to purchase and maintain insurance
on behalf of any person who is or was a director, officer, employee or agent of
the Corporation, or is or was serving at the request of the Corporation as a
director,
 
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officer, employee or agent of another corporation, partnership, joint venture,
trust or other enterprise against any expense, liability or loss incurred by
such person in any such capacity or arising out of such person's status as such,
whether or not the Corporation would have the power to indemnify such person
against such liability under Delaware Law.
 
         (4) The rights and authority conferred in this ARTICLE EIGHTH shall not
be exclusive of any other right which any person may otherwise have or hereafter
acquire.
 
         (5) Neither the amendment nor repeal of this ARTICLE EIGHTH, nor the
adoption of any provision of this Certificate of Incorporation or the bylaws of
the Corporation, nor, to the fullest extent permitted by Delaware Law, any
modification of law, shall eliminate or reduce the effect of this ARTICLE EIGHTH
in respect of any acts or omissions occurring prior to such amendment, repeal,
adoption or modification.
 
         NINTH: Special meetings of the stockholders may be called by the Board
of Directors or the Chairman of the Board of Directors or by the Secretary of
the Corporation pursuant to the Bylaws and may not be called by any other
person. Notwithstanding the foregoing, whenever holders of one or more classes
or series of Preferred Stock shall have the right, voting separately as a class
or series, to elect directors, such holders may call, pursuant to the terms of
the resolution or resolutions adopted by the Board of Directors pursuant to
ARTICLE FOURTH hereto, special meetings of holders of such Preferred Stock.
 
         TENTH: The Corporation reserves the right to amend this Certificate of
Incorporation in any manner permitted by Delaware Law and, with the sole
exception of those rights and powers conferred under the above ARTICLE EIGHTH,
all rights and powers conferred herein on stockholders, directors and officers,
if any, are subject to this reserved power.
 
         ELEVENTH: The Corporation expressly elects not to be governed by
Section 203 of Delaware Law.
 
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<PAGE>
 
         IN WITNESS WHEREOF, the undersigned has caused this Amended and
Restated Certificate of Incorporation to be duly executed in its corporate name
by its duly authorized officer.
 
Dated: March 2, 2004
 
                                ULTRA CLEAN HOLDINGS, INC.
 
                                By:        /s/ Kevin L. Griffin
                                    ----------------------------------
                                    Name:   Kevin L. Griffin
                                    Title:  Secretary
 
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