Exhibit 10.4

EXECUTION COPY

SECURITIES PLEDGE AGREEMENT

     This SECURITIES PLEDGE AGREEMENT (this “Agreement”) is made as of June 29,
2006, by and between ULTRA CLEAN HOLDINGS, INC., a Delaware corporation
(“Pledgor”), in favor of SILICON VALLEY BANK, a California corporation (
“Bank”).

     WHEREAS, Ultra Clean Technology Systems and Service, Inc., a California
corporation (“Ultra Clean”), Bob Acquisition Inc. (and any successor by merger),
a California corporation (“Bob”), Pete Acquisition LLC (to be renamed UCT Sieger
Engineering LLC), a Delaware limited liability company (“Sieger”, together with
Ultra Clean and Bob, “Borrowers”) and Bank are parties to that certain Loan and
Security Agreement, dated as of the date hereof (as amended, modified,
supplemented or restated and in effect from time to time, the “Loan Agreement”).

      WHEREAS, Pledgor is the direct legal and beneficial owner of all of the
issued and outstanding capital stock, all of the units of outstanding membership
interests or other equity interests, as the case may be, of each of the entities
set forth on Annex A hereto (the “Subsidiaries”); and

     WHEREAS, it is a condition precedent to Bank making any Credit Extensions
or otherwise extending credit to Borrowers under the Loan Agreement that Pledgor
execute and deliver to Bank a pledge agreement in substantially the form hereof;
and

     WHEREAS, Pledgor wishes to grant pledges and security interests in favor of
Bank as herein provided.

     NOW, THEREFORE, in consideration of the premises contained herein and for
other good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the parties hereto agree as follows:

     1. Pledge of Securities, etc.

>      1.1. Pledge of Securities. Pledgor hereby pledges, assigns and grants a
> security interest in, mortgages, collaterally assigns and delivers to Bank all
> the right, title and interest of Pledgor in and to all of the shares of
> capital stock, partnership interests, limited liability company membership
> units or other units of equity ownership of every class of each of its
> Subsidiaries, wherever located and whether now owned or hereafter acquires or
> arising, as more fully described on Annex A hereto, including without
> limitation, with respect to any Subsidiary which is a limited liability
> company or a partnership, (a) all payments or distributions, whether in cash,
> property or otherwise, at any time owing or payable to Pledgor on account of
> its interest as a member or as a partner, as the case may be, in any of its
> Subsidiaries or in the nature of a management, investment banking or other fee
> paid or payable by any of the Subsidiaries to Pledgor, (b) all of Pledgor’s
> rights and interests under each of the partnership agreements or operating
> agreements, as applicable, including all voting and management rights and all
> rights to grant or withhold consents or approvals, (c) all rights of access
> and inspection to and use of all books and records, including computer
> software and computer software programs, of each of the Subsidiaries, (d) all
> other rights, interests, property or claims to which Pledgor may be entitled
> in its capacity as the sole member of any Subsidiary of Pledgor, and (e) all
> proceeds, income from, increases in and products of any of the foregoing to be
> held by Bank subject to the terms and conditions hereinafter set forth. The
> certificates for

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> such shares, membership units, partnership interests or other units of equity
> ownership of every class of the capital stock or other equity interest of its
> Subsidiaries, to the extent that such interests are represented by
> certificates, accompanied by stock powers or other appropriate instruments of
> assignment thereof duly executed in blank by Pledgor, have been delivered to
> Bank. Notwithstanding the foregoing, Pledgor shall not be required to pledge
> more than sixty-five percent (65%) of the shares of capital stock, partnership
> interests, limited liability company membership units or other units of equity
> ownership of every class of any of its Foreign Subsidiaries. Pledgor further
> represents and warrants that none of the limited liability company membership
> units or the partnership interests of Pledgor issued by any Subsidiary is a
> security governed by Article 8 of the Uniform Commercial Code of the
> jurisdiction in which such Subsidiary is organized.
> 
>      1.2. Additional Securities. In case Pledgor shall acquire any additional
> capital stock or other equity interest of any Subsidiary of Pledgor or any
> newly-created or acquired Subsidiary or corporation, partnership, limited
> liability company or other entity which is the successor of any Subsidiary of
> Pledgor, or any securities exchangeable for or convertible into shares of such
> capital stock or other equity interest of any class of any Subsidiary of
> Pledgor, by purchase, stock dividend, stock split or otherwise, then Pledgor
> shall forthwith deliver to and pledge such capital stock or other equity
> interests shall be subject to the pledge, assignment and security interest
> granted to Bank under this Agreement and shall deliver to Bank forthwith any
> certificates therefor, accompanied by stock powers or other appropriate
> instruments of assignment duly executed by Pledgor in blank. Pledgor agrees
> that Bank may from time to time attach as Annex A hereto an updated list of
> the shares of capital stock or other equity interests at the time pledged with
> Bank hereunder. Notwithstanding the foregoing, Pledgor shall not be required
> to pledge more than sixty-five percent (65%) of the shares of capital stock,
> partnership interests, limited liability company membership units or other
> units of equity ownership of every class of any of its Foreign Subsidiaries.
> 
>      1.3. Pledge of Cash Collateral Account. Pledgor also hereby pledges,
> assigns, grants a security interest in, and delivers to Bank the Cash
> Collateral Account and all of the Cash Collateral as such terms are
> hereinafter defined.
> 
>      1.4. Waiver of Certain Operating Agreement Provisions. To the extent
> permitted by applicable law, Pledgor irrevocably waives any and all provisions
> of the operating agreements of each Subsidiary of Pledgor (as applicable) that
> (a) prohibit, restrict, condition or otherwise affect the grant hereunder of
> any Lien on any of the Securities Collateral or any enforcement action which
> may be taken in respect of any such Lien or (b) otherwise conflict with the
> terms of this Agreement.

     2. Definitions. The term “Obligations” and all other capitalized terms used
herein without definition shall have the respective meanings provided therefor
in the Loan Agreement. Terms used herein and not defined in the Loan Agreement
or otherwise defined herein that are defined in the Uniform Commercial Code as
in effect in the State of California (the “UCC”) have such defined meanings
herein (with terms used in Article 9 controlling over terms used in another
Article), unless the context otherwise indicates or requires, and the following
terms shall have the following meanings:

     Cash Collateral. See Section 4.

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     Cash Collateral Account. See Section 4.

     Securities. Includes the shares of stock, membership interests, partnership
interests or other equity interests described in Annex A attached hereto and any
additional shares of stock, membership interests, partnership interests or other
equity interests at the time pledged with Bank hereunder and the interests
described in clauses (a)-(e) of Section 1.1 of this Agreement.

     Securities Collateral. The property at any time pledged to Bank hereunder
(whether described herein or not) and all income therefrom, increases therein
and proceeds thereof, including without limitation that included in Cash
Collateral. The term does not include any income, increases or proceeds received
by Pledgor to the extent expressly permitted by Section 6.

     Time Deposits. See Section 4.

     3. Security for Obligations. This Agreement and the security interest in
and pledge of the Securities Collateral hereunder are made with and granted to
Bank as security for the payment and performance in full of all the Obligations
(including all such Obligations which would become due but for the operation of
the automatic stay pursuant to §362(a) of the Bankruptcy Code of the United
States and the operation of §§502(b) and 506(b) of the Bankruptcy Code of the
United States).

     4. Liquidation, Recapitalization, etc.

>      4.1. Distributions Paid to Bank. Any sums or other property paid or
> distributed upon or with respect to any of the Securities, whether by dividend
> or redemption or upon the liquidation or dissolution of the issuer thereof or
> otherwise, shall, except to the extent provided in Section 6, be paid over and
> delivered to Bank as security for the payment and performance in full of all
> of the Obligations. In case, pursuant to the recapitalization or
> reclassification of the capital of the issuer thereof or pursuant to the
> reorganization thereof, any distribution of capital shall be made on or in
> respect of any of the Securities or any property shall be distributed upon or
> with respect to any of the Securities, the property so distributed shall be
> delivered to Bank to be held by it as security for the Obligations. Except to
> the extent provided in Section 6, all sums of money and property paid or
> distributed in respect of the Securities, whether as a dividend or upon such a
> liquidation, dissolution, recapitalization or reclassification or otherwise,
> that are received by Pledgor shall, until paid or delivered to Bank, be held
> in trust for Bank as security for the payment and performance in full of all
> of the Obligations.
> 
>      4.2. Cash Collateral Account. All sums of money that are delivered to
> Bank pursuant to this Section 4 shall be deposited into an interest bearing
> account with Bank or, if Bank is not the depositary bank, to an interest
> bearing account in the name of Bank as customer with a depositary bank
> satisfactory to Bank (any such account, whether maintained with Bank or in
> Bank’s name as customer being herein referred to as the “Cash Collateral
> Account”). Some or all of the funds from time to time in the Cash Collateral
> Account may be invested in time deposits, including, without limitation,
> certificates of deposit issued by Bank (such certificates of deposit or other
> time deposits being hereinafter referred to, collectively, as “Time
> Deposits”), that are satisfactory to Bank after consultation with Pledgor,
> provided, that, in each such case, arrangements satisfactory to Bank are made
> and are in place to perfect and to insure the first priority of Bank’s
> security interest therein. Interest earned on the Cash Collateral Account and
> on

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> the Time Deposits, and the principal of the Time Deposits at maturity that is
> not invested in new Time Deposits, shall be deposited in the Cash Collateral
> Account. The Cash Collateral Account, all sums from time to time standing to
> the credit of the Cash Collateral Account, any and all Time Deposits, any and
> all instruments or other writings evidencing Time Deposits and any and all
> proceeds or any thereof are hereinafter referred to as the “Cash Collateral.”
> 
>      4.3. Pledgor’s Rights to Cash Collateral, etc. Except as otherwise
> expressly provided in Section 16, Pledgor shall not have the right to withdraw
> sums from the Cash Collateral Account, to receive any of the Cash Collateral
> or to require Bank to part with Bank’s possession of any instruments or other
> writings evidencing any Time Deposits.

     5. Warranty of Title; Authority. Pledgor hereby represents and warrants
that: (a) Pledgor has good and marketable title to, and is the sole record and
beneficial owner of, the Securities described in Section 1, subject to no
pledges, liens, security interests, charges, options, restrictions or other
encumbrances except the pledge and security interest created by this Agreement
or Permitted Liens described in clauses (b) and (h) of the definition thereof,
(b) Pledgor has tendered to Bank the consent of any other partner of any
Subsidiary which is a partnership or member or manager of any Subsidiary which
is a limited liability company deemed necessary or appropriate by Pledgor for
consummation of the transactions contemplated hereby, (c) all of the Securities
described in Section 1 are validly issued, fully paid and non-assessable (or the
foreign equivalent thereof, as applicable), (d) Pledgor has full power,
authority and legal right to execute, deliver and perform its obligations under
this Agreement and to pledge and grant a security interest in all of the
Securities Collateral pursuant to this Agreement, and the execution, delivery
and performance hereof and the pledge of and granting and enforcement (where
applicable) of a security interest in the Securities Collateral hereunder have
been duly authorized by all necessary corporate or other action and do not
contravene any law, rule or regulation or any provision of Pledgor’s charter
documents, operating agreement, partnership agreement, by-laws or other
governing document or of any judgment, decree or order of any tribunal or of any
agreement or instrument to which Pledgor is a party or by which it or any of its
property is bound or affected or constitute a default thereunder, and (e) the
information set forth in Annex A hereto relating to the Securities is true,
correct and complete in all respects. Pledgor covenants that it will defend the
rights of Bank and security interest of Bank in such Securities against the
claims and demands of all other persons whomsoever. Pledgor further covenants
that it will have the like title to and right to pledge and grant a security
interest in the Securities Collateral hereafter pledged or in which a security
interest is granted to Bank hereunder and will likewise defend the rights,
pledge and security interest thereof and therein of Bank.

     6. Dividends, Voting, etc., Prior to Maturity. So long as no Event of
Default shall have occurred and be continuing, Pledgor shall be entitled to
receive all cash dividends or distributions paid in respect of the Securities,
to vote the Securities (subject to the last sentence of this paragraph) and to
give consents, waivers and ratifications in respect of the Securities; provided,
however, that no vote shall be cast or consent, waiver or ratification given by
Pledgor if the effect thereof could reasonably be expected to impair any of the
Securities Collateral or be inconsistent with or result in any violation of any
of the provisions of the Loan Agreement or any of the other Loan Documents. All
such rights of Pledgor to receive cash dividends or distributions shall cease in
case a Default or an Event of Default shall have occurred and be continuing. All
such rights of Pledgor to vote and give consents, waivers and ratifications with

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respect to the Securities shall, at Bank’s option, as evidenced by Bank
notifying Pledgor of such election, cease in case a Default or an Event of
Default shall have occurred and be continuing.

     7. Remedies.

>      7.1. In General. If an Event of Default shall have occurred and be
> continuing, Bank shall thereafter have the following rights and remedies (to
> the extent permitted by applicable law) in addition to the rights and remedies
> of a secured party under the UCC, all such rights and remedies being
> cumulative, not exclusive, and enforceable alternatively, successively or
> concurrently, at such time or times as Bank deems expedient:
> 
> >      (a) if Bank so elects and gives notice of such election to Pledgor,
> > Bank may exercise any management or voting rights relating to the Securities
> > (whether or not the same shall have been transferred into its name or the
> > name of its nominee or nominees) for any lawful purpose, including, without
> > limitation, if Bank so elects, for the liquidation of the assets of the
> > issuer thereof or for the amendment or modification of any of the charter,
> > by-laws, operating agreements, partnership agreements or other governing
> > documents, and give all consents, waivers and ratifications in respect of
> > the Securities and otherwise act with respect thereto as though it were the
> > outright owner thereof (Pledgor hereby irrevocably constituting and
> > appointing Bank its proxy and attorney-in-fact, with full power of
> > substitution, to do so);
> > 
> >      (b) Bank may demand, sue for, collect or make any compromise or
> > settlement Bank deems suitable in respect of any Securities Collateral;
> > 
> >       (c) Bank may sell, resell, assign and deliver, or otherwise dispose of
> > any or all of the Securities Collateral, for cash or credit or both and upon
> > such terms at such place or places, at such time or times and to such
> > entities or other persons as Bank thinks expedient, all without demand for
> > performance by Pledgor or any notice or advertisement whatsoever except as
> > expressly provided herein or as may otherwise be required by law;
> > 
> >      (d) Bank may cause all or any part of the Securities held by it to be
> > transferred into its name or the name of its nominee or nominees; and
> > 
> >      (e) Bank may set off or otherwise apply or credit against the
> > Obligations any and all sums deposited with it or held by it, including
> > without limitation, any sums standing to the credit of the Cash Collateral
> > Account and any Time Deposits issued by Bank, with any withdrawal penalty
> > relating to Time Deposits being an expense of collection..
> 
>      7.2. Sale of Securities Collateral. In the event of any sale or other
> disposition of the Securities Collateral as provided in clause (c) of Section
> 7.1, and to the extent that any notice thereof is required to be given by law,
> Bank shall give to Pledgor at least five (5) Business Days prior authenticated
> notice of the time and place of any public sale or other disposition of the
> Securities Collateral or of the time after which any private sale or any other
> intended disposition is to be made. Pledgor hereby acknowledges that five (5)
> Business Days prior authenticated notice of such sale or other disposition or
> sales

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> or other dispositions shall be reasonable notice. Bank may enforce its rights
> hereunder without any other notice and without compliance with any other
> condition precedent now or hereunder imposed by statute, rule of law or
> otherwise (all of which are hereby expressly waived by Pledgor, to the fullest
> extent permitted by law). Bank may buy or otherwise acquire any part or all of
> the Securities Collateral at any public sale or other disposition and if any
> part or all of the Securities Collateral is of a type customarily sold or
> otherwise disposed of in a recognized market or is of the type which is the
> subject of widely-distributed standard price quotations, Bank may buy or
> otherwise acquire at private sale or other disposition and may make payments
> thereof by any means. Bank may apply the cash proceeds actually received from
> any sale or other disposition to the reasonable expenses of retaking, holding,
> preparing for sale, selling and the like, to reasonable attorneys’ fees,
> travel and all other expenses which may be incurred by Bank in attempting to
> collect the Obligations or to enforce this Agreement or in the prosecution or
> defense of any action or proceeding related to the subject matter of this
> Agreement, and then to the Obligations pursuant to Section 9.4 of the Loan
> Agreement. Only after such applications, and after payment by Bank of any
> amount required by §9-608(a)(1)(C) or §9-615(a)(3) of the UCC, need Bank
> account to Pledgor for any surplus.
> 
>      7.3. Registration of Securities. If Bank shall determine to exercise its
> right to sell or otherwise dispose of any or all of the Securities pursuant to
> this Section 7, and if in the opinion of counsel for Bank it is necessary, or
> if in the reasonable opinion of Bank it is advisable, to have the Securities,
> or that portion thereof to be sold, registered under the provisions of the
> Securities Act of 1933, as amended (the “Securities Act”), Pledgor agrees to
> use its best efforts to cause the issuer or issuers of the Securities
> contemplated to be sold, to execute and deliver, and cause the directors (or
> other analogous persons) and officers of such issuer to execute and deliver,
> all at Pledgor’s expense, all such instruments and documents, and to do or
> cause to be done all such other acts and things as may be necessary or, in the
> reasonable opinion of Bank, advisable to register such Securities under the
> provisions of the Securities Act and to cause the registration statement
> relating thereto to become effective and to remain effective for a period of
> nine (9) months from the date such registration statement became effective,
> and to make all amendments thereto or to the related prospectus or both that,
> in the reasonable opinion of Bank, are necessary or advisable, all in
> conformity with the requirements of the Securities Act and the rules and
> regulations of the Securities and Exchange Commission applicable thereto.
> Pledgor agrees to use its best efforts to cause such issuer or issuers to
> comply with the provisions of the securities or “Blue Sky” laws of any
> jurisdiction which Bank shall designate and to cause such issuer or issuers to
> make available to its security holders, as soon as practicable, an earnings
> statement which will satisfy the provisions of Section 11(a) of the Securities
> Act.
> 
>      7.4. Private Sales. Pledgor recognizes that Bank may be unable to effect
> a public sale or other disposition of the Securities by reason of certain
> prohibitions contained in the Securities Act, federal banking laws, and other
> applicable laws, but may be compelled to resort to one or more private sales
> thereof to a restricted group of purchasers. Pledgor agrees that any such
> private sales may be at prices and other terms less favorable to the seller
> than if sold at public sales and that such private sales shall not by reason
> thereof be deemed not to have been made in a commercially reasonable manner.
> Bank shall be under no obligation to delay a sale of any of the Securities for
> the period of time necessary to permit the issuer of such securities to
> register such securities for public sale under the Securities Act, or such
> other federal banking or other applicable

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> laws, even if the issuer would agree to do so. Subject to the foregoing, Bank
> agrees that any sale of the Securities shall be made in a commercially
> reasonable manner, and Pledgor agrees to use its best efforts to cause the
> issuer or issuers of the Securities contemplated to be sold, to execute and
> deliver, and cause the directors (or other analogous persons) and officers of
> such issuer to execute and deliver, all at Pledgor’s expense, all such
> instruments and documents, and to do or cause to be done all such other acts
> and things as may be necessary or, in the reasonable opinion of Bank,
> advisable to exempt such Securities from registration under the provisions of
> the Securities Act, and to make all amendments to such instruments and
> documents which, in the opinion of Bank, are necessary or advisable, all in
> conformity with the requirements of the Securities Act and the rules and
> regulations of the Securities and Exchange Commission applicable thereto.
> Pledgor further agrees to use its best efforts to cause such issuer or issuers
> to comply with the provisions of the securities or “Blue Sky” laws of any
> jurisdiction which Bank shall designate and, if required, to cause such issuer
> or issuers to make available to its security holders, as soon as practicable,
> an earnings statement (which need not be audited) which will satisfy the
> provisions of Section 11(a) of the Securities Act.
> 
>      7.5. Pledgor’s Agreements, etc. Pledgor further agrees to do or cause to
> be done all such other acts and things as may be reasonably necessary on the
> part of Pledgor or with respect to the issuer of the Securities to make any
> sales of any portion or all of the Securities pursuant to this Section 7 valid
> and binding and in compliance with any and all applicable laws (including,
> without limitation, the Securities Act, the Securities Exchange Act of 1934,
> as amended, the rules and regulations of the Securities and Exchange
> Commission applicable thereto and all applicable state securities or “Blue
> Sky” laws), regulations, orders, writs, injunctions, decrees or awards of any
> and all courts, arbitrators or governmental instrumentalities, domestic or
> foreign, having jurisdiction over any such sale or sales, all at Pledgor’s
> expense. Pledgor further agrees that a breach of any of the covenants
> contained in this Section 7 will cause irreparable injury to Bank, that Bank
> has no adequate remedy at law in respect of such breach and, as a consequence,
> agrees that each and every covenant contained in this Section 7 shall be
> specifically enforceable against Pledgor by Bank and Pledgor hereby waives and
> agrees not to assert any defenses against an action for specific performance
> of such covenants to the extent it lawfully may.

     8. Marshalling. Bank shall not be required to marshal any present or future
collateral security for (including but not limited to this Agreement and the
Securities Collateral), or other assurances of payment of, the Obligations or
any of them, or to resort to such collateral security or other assurances of
payment in any particular order. All of Bank’s rights hereunder in respect of
such collateral security and other assurances of payment shall be cumulative and
in addition to all other rights, however existing or arising. To the extent that
it lawfully may, Pledgor hereby agrees that it will not invoke any law relating
to the marshalling of collateral that might cause delay in or impede the
enforcement of Bank’s rights under this Agreement or under any other instrument
evidencing any of the Obligations or under which any of the Obligations is
outstanding or by which any of the Obligations is secured or payment thereof is
otherwise assured, and to the extent that it lawfully may Pledgor hereby
irrevocably waives the benefits of all such laws.

     9. Pledgor’s Obligations Not Affected. The obligations of Pledgor hereunder
shall remain in full force and effect without regard to, and shall not be
impaired by (a) any

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exercise or nonexercise, or any waiver, by Bank of any right, remedy, power or
privilege under or in respect of any of the Obligations or any security thereof
(including this Agreement); (b) any amendment to or modification of the Loan
Agreement, the other Loan Documents or any of the Obligations; (c) any amendment
to or modification of any instrument (other than this Agreement) securing any of
the Obligations, including, without limitation, any pledge agreement, security
agreement or other collateral document delivered under or in connection with the
Loan Agreement; or (d) the taking of additional security for, or any other
assurances of payment of, any of the Obligations or the release or discharge or
termination of any security or other assurances of payment or performance for
any of the Obligations; whether or not Pledgor shall have notice or knowledge of
any of the foregoing, Pledgor hereby generally waiving all suretyship defenses
to the extent applicable. Under no circumstances shall Bank be deemed to be a
shareholder, member or other equity holder of any of the Subsidiaries by virtue
of the provisions of this Agreement unless expressly agreed to in writing by
Bank.

     10. Transfer, etc., by Pledgor. Except as expressly permitted under the
Loan Agreement, without the prior written consent of Bank, Pledgor will not
sell, assign, transfer or otherwise dispose of, grant any option with respect
to, or pledge or grant any security interest in or otherwise encumber or
restrict any of the Securities Collateral or any interest therein, except for
the pledge thereof and security interest therein provided for in this Agreement
and Permitted Liens described in clauses (b) and (h) of the definition thereof.

     11. Further Assurances. Pledgor will do all such acts, and will furnish to
Bank all such financing statements, certificates, legal opinions and other
documents and will obtain all such governmental consents and corporate approvals
and will do or cause to be done all such other things as Bank may reasonably
request from time to time in order to give full effect to this Agreement and to
secure the rights of Bank hereunder, all without any cost or expense to Bank.
Pledgor hereby irrevocably authorizes Bank at any time and from time to time to
file in any filing office in any Uniform Commercial Code jurisdiction any
initial financing statements and amendments thereto that (a) indicate the
Collateral as the Securities Collateral or words of similar effect, or as being
of equal or lesser scope or in greater detail, and (b) contain any other
information required by part 5 of Article 9 of the Uniform Commercial Code of
the jurisdiction of the filing office for the sufficiency or filing office
acceptance of any financing statement or amendment, including whether Pledgor is
an organization, the type of organization and any organization identification
number issued to Pledgor. Pledgor agrees to furnish any such information to Bank
promptly upon request. Pledgor also ratifies its authorization for Bank to have
filed in any Uniform Commercial Code jurisdiction any like initial financing
statements or amendments thereto if filed prior to the date hereof. Pledgor will
not permit to be effected any amendment or modification of the charter, by-laws,
operating agreements, or other applicable organizational documents of Pledgor or
any of the Subsidiaries which would (or would be reasonably likely to) adversely
affect the rights or remedies of Bank hereunder or the value of the Securities
Collateral.

     12. Bank’s Exoneration. Under no circumstances shall Bank be deemed to
assume any responsibility for or obligation or duty with respect to any part or
all of the Securities Collateral of any nature or kind or any matter or
proceedings arising out of or relating thereto, other than (a) to exercise
reasonable care in the physical custody of the Securities Collateral and (b)
after a Default or an Event of Default shall have occurred and be continuing to
act in a commercially reasonable manner. Bank shall not be required to take any
action of any kind to collect, preserve or protect its or Pledgor’s rights in
the Securities Collateral or against other parties thereto. Bank’s prior
recourse to any part or all of the Securities Collateral shall not

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constitute a condition of any demand, suit or proceeding for payment or
collection of any of the Obligations. This Agreement constitutes a pledge of the
Securities Collateral and any other applicable collateral hereunder only, and
not an assignment of any duties or obligations of Pledgor with respect thereto,
and by its acceptance hereof and whether or not Bank shall have exercised any of
its rights or remedies hereunder, Bank does not undertake to perform or
discharge, and Bank shall not be responsible or liable for the performance or
discharge of any such duties or responsibilities, including, without limitation,
for any capital calls. Pledgor agrees that, notwithstanding the exercise by Bank
of any of its rights hereunder, Pledgor shall remain liable nonetheless for the
full and prompt performance of all of Pledgor’s obligations and liabilities
under any operating agreement, limited partnership agreement, or similar
document evidencing or governing any units of membership interest or limited
partnership interest in any limited liability company or limited partnership
included in the Securities Collateral. Under no circumstances shall Bank or any
holder of any of the Obligations as such be deemed to be a member, limited
partner, or other equity owner of any of the Subsidiaries by virtue of the
provisions of this Agreement unless expressly agreed to in writing by Bank or
such holder. Without limiting the generality of the foregoing, Bank shall not
have any fiduciary duty as such to Pledgor or any other equity owner of any of
its Subsidiaries by reason of this Agreement, whether by virtue of the security
interests and liens hereunder, or any enforcement action in respect of such
security interests and liens, unless and until Bank is actually admitted to the
applicable Subsidiary as a substitute member or substitute equity owner thereof
after exercising enforcement rights under part 6 of Article 9 of the Uniform
Commercial Code in effect in the applicable jurisdiction, or otherwise.

     13. No Waiver, etc. Except as provided in Section 1.2 hereof with respect
to any updated list of the shares of capital stock or other equity interests,
neither this Agreement nor any term hereof may be changed, waived, discharged or
terminated except by a written instrument expressly referring to this Agreement
and to the provisions so modified or limited, and executed by Bank and Pledgor.
No act, failure or delay by Bank shall constitute a waiver of its rights and
remedies hereunder or otherwise. No single or partial waiver by Bank of any
default or right or remedy that it may have shall operate as a waiver of any
other default, right or remedy or of the same default, right or remedy on a
future occasion. Pledgor hereby waives presentment, notice of dishonor and
protest of all instruments, included in or evidencing any of the Obligations or
the Securities Collateral, and any and all other notices and demands whatsoever
(except as expressly provided herein or in the Loan Agreement).

     14. Registration and Filing. Pledgor (a) has caused each Subsidiary of
Pledgor to duly register the security interests granted hereby on the respective
books of such Subsidiary and has furnished Bank with evidence thereof, (b) has
duly executed and caused any financing statements with respect to the Securities
Collateral to be filed in such a manner and in such places as may be required by
law in order to fully protect the rights of Bank hereunder, and (c) will cause
any financing statements with respect to the Securities Collateral at all times
to be kept recorded and filed at each of the respective Subsidiaries’ expense in
such a manner and in such places as may be required by law in order to fully
perfect the interests and protect the rights of Bank hereunder.

     15. Notice, etc. All notices, requests and other communications hereunder
shall be made in the manner set forth in Section 9 of the Guaranty.

     16. Termination. Upon final payment and performance in full in cash of the
Obligations (other than inchoate indemnity obligations and any other obligations
which, by their

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terms, are to survive the termination of any of the Loan Documents) and the
termination of all lending and other credit commitments of Bank in respect
thereof (including all outstanding Letters of Credit), this Agreement shall
terminate and Bank shall, at Pledgor’s request and expense, return such
Securities Collateral in the possession or control of Bank as has not
theretofore been disposed of pursuant to the provisions hereof, together with
any moneys and other property at the time held by Bank hereunder.

     17. Overdue Amounts. Until paid, all amounts due and payable by Pledgor
hereunder shall be a debt secured by the Securities Collateral and shall bear,
whether before or after judgment, interest at the rate of interest for overdue
principal set forth in the Loan Agreement.

     18. General. In any action or proceeding between Pledgor and Bank arising
out of or relating to this Agreement, the prevailing party shall be entitled to
recover its reasonable attorneys’ and other costs and expenses incurred, in
addition to any other relief to which it may be entitled. All amendments to this
Agreement must be in writing signed by both Bank and Pledgor. This Agreement may
be executed in any number of counterparts and by different parties on separate
counterparts, each of which, when executed and delivered, are an original, and
all taken together, constitute one Agreement. To the extent that any provision
of this Agreement conflicts with any provision of the Loan Agreement, the
provision giving Bank greater rights or remedies shall govern, it being
understood that the purpose of this Agreement is to add to, and not detract
from, the rights granted to Bank under the Loan Agreement. This Agreement, the
Loan Agreement and the other Loan Documents represent the entire agreement about
this subject matter and supersede prior negotiations or agreements. All prior
agreements, understandings, representations, warranties, and negotiations
between the parties about the subject matter of this Agreement, the Loan
Agreement and the other Loan Documents merge into this Agreement, the Loan
Agreement and the other Loan Documents.

     19. Choice Of Law, Venue and Jury Trial Waiver. California law governs this
Agreement without regard to principles of conflicts of law. Pledgor and Bank
each submit to the exclusive jurisdiction of the State and Federal courts in
Santa Clara County, California; provided, however, that nothing in this
Agreement shall be deemed to operate to preclude Bank from bringing suit or
taking other legal action in any other jurisdiction to realize on the Collateral
or any other security for the Obligations, or to enforce a judgment or other
court order in favor of Bank. Pledgor expressly submits and consents in advance
to such jurisdiction in any action or suit commenced in any such court, and
Pledgor hereby waives any objection that it may have based upon lack of personal
jurisdiction, improper venue, or forum non conveniens and hereby consents to the
granting of such legal or equitable relief as is deemed appropriate by such
court. Pledgor hereby waives personal service of the summons, complaints, and
other process issued in such action or suit and agrees that service of such
summons, complaints, and other process may be made by registered or certified
mail addressed to Pledgor at the address set forth in Section 9 of the Guaranty
and that service so made shall be deemed completed upon the earlier to occur of
Pledgor’s actual receipt thereof or three (3) days after deposit in the U.S.
mails, proper postage prepaid.

     TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW PLEDGOR AND BANK EACH
WAIVE THEIR RIGHT TO A JURY TRIAL OF ANY CLAIM OR CAUSE OF ACTION ARISING OUT OF
OR BASED UPON THIS AGREEMENT, INCLUDING CONTRACT, TORT, BREACH OF DUTY AND ALL
OTHER CLAIMS. THIS WAIVER IS A

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MATERIAL INDUCEMENT FOR BOTH PARTIES TO ENTER INTO THIS AGREEMENT. EACH PARTY
HAS REVIEWED THIS WAIVER WITH ITS COUNSEL.

     WITHOUT INTENDING IN ANY WAY TO LIMIT THE PARTIES’ AGREEMENT TO WAIVE THEIR
RESPECTIVE RIGHT TO A TRIAL BY JURY, if the above waiver of the right to a trial
by jury is not enforceable, the parties hereto agree that any and all disputes
or controversies of any nature between them arising at any time shall be decided
by a reference to a private judge, mutually selected by the parties (or, if they
cannot agree, by the Presiding Judge of the Santa Clara County, California
Superior Court) appointed in accordance with California Code of Civil Procedure
Section 638 (or pursuant to comparable provisions of federal law if the dispute
falls within the exclusive jurisdiction of the federal courts), sitting without
a jury, in Santa Clara County, California; and the parties hereby submit to the
jurisdiction of such court. The reference proceedings shall be conducted
pursuant to and in accordance with the provisions of California Code of Civil
Procedure §§ 638 through 645.1, inclusive. The private judge shall have the
power, among others, to grant provisional relief, including without limitation,
entering temporary restraining orders, issuing preliminary and permanent
injunctions and appointing receivers. All such proceedings shall be closed to
the public and confidential and all records relating thereto shall be
permanently sealed. If during the course of any dispute, a party desires to seek
provisional relief, but a judge has not been appointed at that point pursuant to
the judicial reference procedures, then such party may apply to the Santa Clara
County, California Superior Court for such relief. The proceeding before the
private judge shall be conducted in the same manner as it would be before a
court under the rules of evidence applicable to judicial proceedings. The
parties shall be entitled to discovery which shall be conducted in the same
manner as it would be before a court under the rules of discovery applicable to
judicial proceedings. The private judge shall oversee discovery and may enforce
all discovery rules and order applicable to judicial proceedings in the same
manner as a trial court judge. The parties agree that the selected or appointed
private judge shall have the power to decide all issues in the action or
proceeding, whether of fact or of law, and shall report a statement of decision
thereon pursuant to the California Code of Civil Procedure § 644(a). Nothing in
this paragraph shall limit the right of any party at any time to exercise
self-help remedies, foreclose against collateral, or obtain provisional
remedies. The private judge shall also determine all issues relating to the
applicability, interpretation, and enforceability of this paragraph.

     20. Name Change of Pete Acquisition to UCT Sieger Engineering LLC.
Substantially simultaneously with the consummation of the Acquisition, the name
of Pete Acquisition LLC shall be changed to UCT Sieger Engineering LLC by filing
such name change with the Secretary of State of the State of Delaware. From and
after such time, all references to Sieger shall mean UCT Sieger Engineering LLC,
a Delaware limited liability company.

[Signature Page Follows]

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     IN WITNESS WHEREOF, intending to be legally bound, Pledgor and Bank have
caused this Agreement to be executed as of the date first above written.

PLEDGOR:   ULTRA CLEAN HOLDINGS, INC.         By:  /s/ Jack Sexton  

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  Name: Jack Sexton   Title: Chief Financial Officer

BANK:   SILICON VALLEY BANK         By:  /s/ Maria Fischer Leaf  

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  Name: Maria Fischer Leaf   Title: Senior Relationship Manager

 

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     The undersigned Subsidiaries hereby join in the above Agreement for the
sole purpose of consenting to and being bound by the provisions of Sections 4.1,
6 and 7 thereof, the undersigned hereby agreeing to cooperate fully and in good
faith with Bank and Pledgor in carrying out such provisions.

Ultra Clean Technology Systems and Service, Inc.
Bob Acquisition Inc. (and any successor by merger)
Pete Acquisition LLC (to be renamed UCT Sieger
Engineering LLC)
Ultra Clean International Holding Company           By:    

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  Name:     Title:  

 

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ANNEX A TO SECURITIES PLEDGE AGREEMENT

     None of the issuers has any authorized, issued or outstanding shares of its
capital stock, membership interests, partnership interests or other equity
interests of any class or any commitments to issue any shares of its capital
stock, membership interests, partnership interests or other equity interests of
any class or any securities convertible into or exchangeable for any shares of
its capital stock, membership interests, partnership interests or other equity
interests of any class except as otherwise stated in this Annex A.

                Number                     Number of   of   Number of   Par or  
  Record   Class of   Authorized   Issued   Outstanding   Liquidation Issuer  
Owner   Shares   Shares   Shares   Shares   Value

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Ultra Clean Technology   Ultra Clean Holdings, Inc.   Common   1,000   1,000  
1,000   No Systems and Service, Inc.                         Bob Acquisition
Inc.   Ultra Clean Holdings, Inc.   Common   1,000   1,000   1,000   No Pete
Acquisition LLC   Ultra Clean Holdings, Inc.   100%   N/A   N/A   N/A   N/A    
    membership                         interest                 Ultra Clean
International   Ultra Clean Holdings, Inc.   Common   100   100   100   No
Holding Company*                        

*only 65% of the shares (which are currently represented by Certificate No. 3)
are being pledged to Bank hereby.

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