Exhibit 10-aaa(5)

> > > > > GUARANTEE AGREEMENT dated as of March 3, 2003 among MEMC ELECTRONIC
> > > > > MATERIALS, INC., a Delaware corporation ("Borrower"), each of the
> > > > > subsidiaries listed on Schedule I hereto (each such subsidiary,
> > > > > individually, a "Subsidiary" or a "Guarantor" and, collectively, the
> > > > > "Subsidiaries" or the "Guarantors") and CITICORP USA, INC. as
> > > > > collateral agent (the "Collateral Agent") for the Secured Parties (as
> > > > > defined in the Security Agreement).

Reference is made to the Revolving Credit Agreement dated as of December 5, 2002
(as amended, supplemented or otherwise modified from time to time, the
"Revolving Credit Agreement"), among the Borrower, the lenders from time to time
party thereto (the "Lenders"), the Collateral Agent and Citicorp USA, Inc., as
administrative agent for the Lenders (in such capacity, the "Administrative
Agent"). Capitalized terms used herein and not defined herein shall have the
meanings assigned to such terms in the Revolving Credit Agreement.

The Lenders have agreed to make Loans to the Borrower pursuant to, and upon the
terms and subject to the conditions specified in, the Revolving Credit
Agreement. Each of the Subsidiaries is a direct or indirect subsidiary of the
Borrower and acknowledges that it will derive substantial benefit from the
making of the Loans by the Lenders. The obligations of the Lenders to make Loans
are conditioned on, among other things, the execution and delivery by the
Guarantors of a Guarantee Agreement in the form hereof. As consideration
therefor and in order to induce the Lenders to make Loans, the Guarantors are
willing to execute this Agreement.

As is set forth in the Revolving Credit Agreement, the Lenders have agreed that
the Indebtedness evidenced by the Loan Documents shall be subordinated in right
of payment to the prior payment in full of the Bank Revolver Obligations, in
accordance with Article X of the Revolving Credit Agreement. The parties hereto
desire that the Guarantees of the Investor Revolver Obligations described herein
should also constitute Subordinated Indebtedness and be subordinated in right of
payment to the prior payment in full of the Bank Revolver Obligations, in
accordance with Article II of this Guarantee Agreement.

Accordingly, the parties hereto agree as follows:

1. Guarantee. Each Guarantor unconditionally guarantees, jointly with the other
Guarantors and severally, as a primary obligor and not merely as a surety, (a)
the due and punctual payment of (i) the principal of and premium, if any, and
interest (including interest accruing during the pendency of any bankruptcy,
insolvency, receivership or other similar proceeding, regardless of whether
allowed or allowable in such proceeding) on the Loans, when and as due, whether
at maturity, by acceleration, upon one or more dates set for prepayment or
otherwise and (ii) all other monetary obligations, including fees, costs,
expenses and indemnities, whether primary, secondary, direct, contingent, fixed
or otherwise (including monetary obligations incurred during the pendency of any
bankruptcy, insolvency, receivership or other similar proceeding, regardless of
whether allowed or allowable in such proceeding), of the Loan Parties to the
Secured Parties under the Revolving Credit Agreement and th e other Loan
Documents, (b) the due and punctual performance of

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    all covenants, agreements, obligations and liabilities of the Loan Parties
under or pursuant to the Revolving Credit Agreement and the other Loan
Documents, (c) unless otherwise agreed to in writing by the applicable Lender
party thereto, the due and punctual payment and performance of all obligations
of the Borrower or any other Loan Party, monetary or otherwise, under each
Hedging Agreement entered into with a counterparty that was a Lender (or an
Affiliate of a Lender) at the time such Hedging Agreement was entered into and
(d) the due and punctual payment and performance of all obligations in respect
of overdrafts and related liabilities owed to the Administrative Agent or any of
its Affiliates and arising from treasury, depositary and cash management
services in connection with any automated clearing house transfers of funds (all
the monetary and other obligations referred to in the preceding clauses (a)
through (d) being collecti vely called the "Investor Revolver Obligations").
Each Guarantor further agrees that the Investor Revolver Obligations may be
extended or renewed, in whole or in part, without notice to or further assent
from it, and that it will remain bound upon its guarantee notwithstanding any
extension or renewal of any Investor Revolver Obligation. Each Guarantor agrees
to pay, in addition to the amounts stated above, any and all expenses (including
reasonable counsel fees and expenses) incurred by the Secured Parties in
enforcing any rights under this Agreement.          2. Investor Revolver
Obligations Not Waived. To the fullest extent permitted by applicable law, each
Guarantor waives presentment to, demand of payment from and protest to the
Borrower of any of the Investor Revolver Obligations, and also waives notice of
acceptance of its guarantee and notice of protest for nonpayment. To the fullest
extent permitted by applicable law, the obligations of each Guarantor hereunder
shall not be affected by (a) the failure of the Collateral Agent or any other
Secured Party to assert any claim or demand or to enforce or exercise any right
or remedy against the Borrower or any Guarantor under the provisions of the
Revolving Credit Agreement, any other Loan Document or otherwise; (b) any
rescission, waiver (except the effect of any waiver obtained pursuant to
Section 3.05(b)), amendment or modification of, or any release from any terms or
provisions of any other Loan Document, any other Guarantee or any other
agreement, including with re spect to any other Guarantor under this Agreement,
(c) the failure to perfect any security interest in, or release of, any of the
security held by or on behalf of the Collateral Agent or any other Secured
Party, or (d) any change in ownership of the Borrower.          3. Security.
Each of the Guarantors authorizes the Collateral Agent and each of the other
Secured Parties to (a) take and hold security for the payment of this Guarantee
and the Investor Revolver Obligations as set forth in the Security Agreement,
and exchange, enforce, waive and release any such security, (b) apply such
security and direct the order or manner of sale thereof as they in their sole
discretion may determine and (c) release or substitute any one or more
endorsees, other Guarantors or other obligors.          4. Guarantee of Payment.
Each Guarantor agrees that its guarantee constitutes a guarantee of payment when
due and not of collection, and waives any right to require that any resort be
had by the Collateral Agent or any other Secured Party to any of the security
held for payment of the Investor Revolver Obligations or to any balance of any
deposit account or credit on the books of the Collateral Agent or any other
Secured Party in favor of the Borrower or any other Person

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>   5. No Discharge or Diminishment of Guarantee. The obligations of each
> Guarantor hereunder shall not be subject to any reduction, limitation,
> impairment or termination for any reason (other than the indefeasible payment
> in full in cash of the Investor Revolver Obligations), including any claim of
> waiver, release, surrender, alteration or compromise of any of the Investor
> Revolver Obligations, and shall not be subject to any defense or setoff,
> counterclaim, recoupment or termination whatsoever by reason of the
> invalidity, illegality or unenforceability of the Investor Revolver
> Obligations or otherwise. Without limiting the generality of the foregoing,
> the obligations of each Guarantor hereunder shall not be discharged or
> impaired or otherwise affected by the failure of the Collateral Agent or any
> other Secured Party to assert any claim or demand or to enforce any remedy
> under the Revolving Credit Agreement, any other Loan Document or any other
> agreement, by any waiver or modification of any provision of any thereof, by
> any default, failure or delay, willful or otherwise, in the performance of the
> Investor Revolver Obligations, or the failure to perfect any security interest
> in, or the release of, any of the security held by or on behalf of the
> Collateral Agent or any other Secured Party, or by any other act or omission
> that may or might in any manner or to any extent vary the risk of any
> Guarantor or that would otherwise operate as a discharge of each Guarantor as
> a matter of law or equity (other than the indefeasible payment in full in cash
> of all the Investor Revolver Obligations).       6. Defenses of Borrower
> Waived. To the fullest extent permitted by applicable law, each of the
> Guarantors waives any defense based on or arising out of any defense of the
> Borrower or the unenforceability of the Investor Revolver Obligations or any
> part thereof from any cause, or the cessation from any cause of the liability
> of the Borrower, other than the final and indefeasible payment in full in cash
> of the Investor Revolver Obligations. The Collateral Agent and the other
> Secured Parties may, at their election, foreclose on any security held by one
> or more of them by one or more judicial or nonjudicial sales, accept an
> assignment of any such security in lieu of foreclosure, compromise or adjust
> any part of the Investor Revolver Obligations, make any other accommodation
> with the Borrower or any other guarantor or exercise any other right or remedy
> available to them against the Borrower or any other guarantor, without
> affecting or impairing in any way the liability of any Guarantor hereunder
> except to the extent the Investor Revolver Obligations have been fully,
> finally and indefeasibly paid in cash. Pursuant to applicable law, each of the
> Guarantors waives any defense arising out of any such election even though
> such election operates, pursuant to applicable law, to impair or to extinguish
> any right of reimbursement or subrogation or other right or remedy of such
> Guarantor against the Borrower or any other Guarantor or guarantor, as the
> case may be, or any security.       7. Agreement to Pay; Subordination. In
> furtherance of the foregoing and not in limitation of any other right that the
> Collateral Agent or any other Secured Party has at law or in equity against
> any Guarantor by virtue hereof, upon the failure of the Borrower or any other
> Loan Party to pay any Investor Revolver Obligations when and as the same shall
> become due, whether at maturity, by acceleration, after notice of prepayment
> or otherwise, each Guarantor hereby promises to and will forthwith pay, or
> cause to be paid, to the Collateral Agent or such other Secured Party as
> designated thereby, in cash the amount equal to the sum of such unpaid
> Investor Revolver Obligations.

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   a. The Guarantee of each Guarantor made hereby is, to the extent and in the
manner set forth in Article II hereof, subordinated and subject in right of
payment to the prior payment in full of all Bank Revolver Obligations of such
Guarantor and is made subject to the provisions of such Article II.         
        b. Upon payment by any Guarantor of any sums to the Collateral Agent or
any Secured Party as provided above, all rights of such Guarantor against the
Borrower arising as a result thereof by way of right of subrogation,
contribution, reimbursement, indemnity or otherwise shall in all respects be
subordinate and junior in right of payment to the prior indefeasible payment in
full in cash of all the Investor Revolver Obligations. If any amount shall
erroneously be paid to any Guarantor on account of such subrogation,
contribution, reimbursement, indemnity or similar right, such amount shall be
held in trust for the benefit of the Secured Parties and shall forthwith be paid
to the Collateral Agent to be credited against the payment of the Investor
Revolver Obligations, whether matured or unmatured, in accordance with the terms
of the Loan Documents.        8. Agreement to Subordinate.  Each of the
Guarantors and the Collateral Agent agrees that the obligations of the
Guarantors under this Agreement shall be subordinated in right of payment, to
the extent and in the manner provided in this Article II, to the prior payment
in full of all Bank Revolver Obligations of such Guarantor and that such
subordination is for the benefit of and enforceable by the Bank Lenders and the
Fund Guarantors. The obligations of each Guarantor hereunder shall in all
respects rank pari passu to all existing and future Indebtedness of such
Guarantor and senior to such Indebtedness of such Guarantor that is, by its
terms, expressly subordinated to such other Indebtedness of the Guarantor; and
only the Bank Revolver Obligations of such Guarantor shall rank senior to the
obligations of such Guarantor hereunder in accordance with the provisions set
forth herein.    9. Liquidation, Dissolution, Bankruptcy. Upon any payment or
distribution of the assets of a Guarantor to creditors upon a total or partial
liquidation or a total or partial dissolution of such Guarantor or in a
bankruptcy, reorganization, insolvency, receivership or similar proceeding
relating to such Guarantor and its property: (a) the Bank Revolver Obligations
of such Guarantor shall be paid in full before the Lenders shall be entitled to
receive any payment pursuant to any Investor Revolver Obligations from such
Guarantor; and   (b) until the Bank Revolver Obligations of such Guarantor are
paid in full, any payment or distribution to which the Lenders would be entitled
but for this Article II shall be made to the Bank Lenders and the Fund
Guarantors as payment of such Bank Revolver Obligations as their respective
interests may appear, except that Lenders may receive shares of stock and any
debt securities that are subordinated to such Bank Revolver Obligations to at
least the same extent as this Agreement. 10. Default on Bank Revolver
Obligations and Payment Blockage. A Guarantor may not make any payment pursuant
to any of the Investor Revolver Obligations at any time when the Borrower is
prohibited from making any payments to the Lenders of any principal of, premium
(if any) or interest on, the Loans pursuant to Section 10.03 of

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> the Revolving Credit Agreement.       11. Demand for Payment. If payment of
> the Loans is accelerated because of an Event of Default and a demand for
> payment is made on a Guarantor, the Collateral Agent shall promptly notify the
> Bank Lenders and the Fund Guarantors (or the Representatives of such Bank
> Lenders and Fund Guarantors) of such demand. If any Bank Revolver Obligations
> of such Guarantor are outstanding, such Guarantor may not pay its Guarantee
> until five (5) Business Days after such Bank Lenders and Fund Guarantors
> receive (or the Representatives of such Bank Lenders and Fund Guarantors
> receive) notice of such demand and thereafter only at such time as this
> Article II otherwise permits.   12. When Distribution Must Be Paid Over. If a
> payment or distribution is made to any Lenders in violation of this Article
> II, any Lender who receives such a payment or distribution shall hold such
> payment or distribution in trust for the Bank Lenders and the Fund Guarantors
> and pay the full amount of such payment or distribution over to such Bank
> Lenders and Fund Guarantors as their respective interests may appear.     13.
> Subrogation. After all Bank Revolver Obligations of a Guarantor are paid in
> full and for so long as any Loans are outstanding, the Lenders shall be
> subrogated to the rights of the Bank Lenders and the Fund Guarantors to
> receive payments or distributions applicable to such Bank Revolver
> Obligations. A distribution or payment made under Section 2.05 hereof to the
> Bank Lenders or the Fund Guarantors under such Guarantor's Guarantee of the
> Investor Revolver Obligations which otherwise would have been payable to the
> Lenders is not, as between such Guarantor and the Lenders, a payment by such
> Guarantor applicable to the Bank Revolver Obligations.       14. Relative
> Rights. This Article II defines the relative rights between the (i) the
> Lenders, on the one hand, and (ii) the Bank Lenders and the Fund Guarantors,
> on the other hand. Nothing in this Guarantee Agreement shall:      
> (a) impair, as between a Guarantor and the Lenders, the obligation of a
> Guarantor, which is absolute and unconditional, to make payments with respect
> to such Guarantor's Guarantee of the Investor Revolver Obligations to the
> extent set forth in Article I; or       (b) prevent the Collateral Agent or
> any Secured Party from exercising its available remedies upon a default by a
> Guarantor under its obligations with respect to the Investor Revolver
> Obligations, subject to the rights of the Bank Lenders and the Fund Guarantors
> under the Bank Revolver Obligations of such Guarantor to receive payments or
> distributions otherwise payable to the Lenders in accordance with Section 2.05
> hereof.       15. Subordination May Not Be Impaired by a Guarantor. No right
> of any Bank Lender or Fund Guarantor under the Bank Revolver Obligations of a
> Guarantor to enforce the subordination of such Guarantor's Guarantee of the
> Investor Revolver Obligations hereunder shall be impaired by any act or
> failure to act by such Guarantor or by its failure to comply with this
> Guarantee Agreement.       16. Rights of Collateral Agent.

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> (a) Notwithstanding Section 2.03, the Collateral Agent may continue to make
> payments pursuant to this Guarantee Agreement and shall not be charged with
> knowledge of the existence of facts that would prohibit the making of any such
> payments unless, not less than two (2) Business Days prior to the date of such
> payment, the Collateral Agent receives written notice satisfactory to it that
> payments may not be made under this Article II. The Borrower, a Guarantor, a
> Representative, a Bank Lender or a Fund Guarantor may give such notice;
> provided, however, that if there is a Representative in respect of the Bank
> Revolver Obligations, only the Representative may give such notice.   (b) The
> Collateral Agent in its individual or any other capacity may be a Bank Lender
> or a Fund Guarantor with the same rights it would have if it were not the
> Collateral Agent. The Collateral Agent shall be entitled to all the rights set
> forth in this Article II with respect to any Bank Revolver Obligations of a
> Guarantor which may at any time be held by it, to the same extent as any other
> Bank Lender or Fund Guarantor; and nothing in Article VIII of the Revolving
> Credit Agreement shall deprive the Collateral Agent of any of its rights as
> such Bank Lender or Fund Guarantor. Nothing in this Article II shall apply to
> claims of, or payments to, the Collateral Agent under or pursuant to
> Section 11.03 of the Revolving Credit Agreement or any other Section of the
> Revolving Credit Agreement.   17. Distribution or Notice to Representative.
> Whenever a payment or distribution is to be made or a notice is to be given to
> the Bank Lenders or the Fund Guarantors in connection with the Revolver
> Obligations of a Guarantor, such payment or distribution may be made, and such
> notice may be given, instead to their Representatives (if any).   18. Article
> II Not to Prevent Events of Default or Limit Right to Accelerate. The failure
> of a Guarantor to make a payment on any of the Investor Revolver Obligations
> by reason of any provision in this Article II shall not be construed as
> preventing the occurrence of a default by such Guarantor under its Guarantee
> of such Investor Revolver Obligations. Nothing in this Article II shall have
> any effect on the right of the Lenders or the Collateral Agent to make a
> demand for payment on a Guarantor in accordance with this Guarantee Agreement.
>   19. Collateral Agent Entitled to Rely. Upon any payment or distribution
> pursuant to this Article II, the Collateral Agent and the Lenders shall be
> entitled to rely (a) upon any order or decree of a court of competent
> jurisdiction in which any proceedings of the nature referred to in
> Section 2.02 are pending, (b) upon a certificate of the liquidating trustee or
> agent or other Person making such payment or distribution to the Collateral
> Agent or to the Lenders or (c) upon the Representatives for the Bank Lenders
> and the Fund Guarantors for the purpose of ascertaining the Persons entitled
> to participate in such payment or distribution, the amount of the Bank
> Revolver Obligations of a Guarantor, the amount or amounts previously paid or
> distributed thereon and all other facts pertinent thereto or to this Article
> II. In the event that the Collateral Agent determines, in good faith, that
> evidence is required with respect to the right of any Person as a holder of
> the Ban k Revolver Obligations of a Guarantor to participate in any payment or
> distribution pursuant to this Article II, the Collateral Agent may request
> such Person to furnish evidence to the reasonable satisfaction of the
> Collateral Agent as to the amount of Bank Revolver Obligations of such
> Guarantor held by such Person, the extent to which such Person is entitled to
> participate in such

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  payment or distribution and other facts pertinent to the rights of such Person
under this Article II, and, if such evidence is not furnished, the Collateral
Agent may defer any payment to such Person pending judicial determination as to
the right of such Person to receive such payment.        20. Collateral Agent to
Effectuate Subordination. Each Lender authorizes and directs the Collateral
Agent on its behalf to take such action as may be necessary or appropriate to
acknowledge or effectuate the subordination between (i) the Lenders, on the one
hand, and (ii) the Bank Lenders and the Fund Guarantors, on the other hand, as
provided in this Article II and appoints the Collateral Agent as
attorney-in-fact for any and all such purposes.        21. Collateral Agent Not
Fiduciary with Respect to Bank Revolver Obligations of a Guarantor. The
Collateral Agent shall not be deemed to owe any fiduciary duty to the Bank
Lenders or the Fund Guarantors and the Collateral Agent shall not be liable to
any such creditors if it shall mistakenly pay over or distribute to the Lenders
or the relevant Guarantor or any other Person, money or assets to which such
creditors shall be entitled by virtue of this Article II or otherwise       22.
Reliance by Bank Lenders and Fund Guarantors. Each Lender acknowledges and
agrees that the foregoing subordination provisions are, and are intended to be,
an inducement and a consideration to any Bank Lender or Fund Guarantor under
Bank Revolver Obligations to extend and continue to extend, or to continue to
extend, such Bank Revolver Obligations, and such Bank Lender or Fund Guarantor
shall be deemed conclusively to have relied on such subordination provisions in
extending and continuing to extend, or in continuing to extend, such Bank
Revolver Obligations.       23. Information. Each of the Guarantors assumes all
responsibility for being and keeping itself informed of the Borrower's financial
condition and assets, and of all other circumstances bearing upon the risk of
nonpayment of the Investor Revolver Obligations and the nature, scope and extent
of the risks that such Guarantor assumes and incurs hereunder, and agrees that
none of the Collateral Agent or the other Secured Parties will have any duty to
advise any of the Guarantors of information known to it or any of them regarding
such circumstances or risks.       24. Representations and Warranties. Each of
the Guarantors represents and warrants as to itself that all representations and
warranties relating to it contained in the Revolving Credit Agreement and other
Loan Documents are true and correct in all material respects.       25.
Termination. The Guarantees made hereunder (a) shall terminate when all the
Investor Revolver Obligations have been performed or indefeasibly paid in full
in cash, as applicable and the Lenders have no further commitment to lend under
the Revolving Credit Agreement, and (b) shall continue to be effective or be
reinstated, as the case may be, if at any time payment, or any part thereof, of
any Investor Revolver Obligations is rescinded or must otherwise be restored by
any Secured Party or any Guarantor upon the bankruptcy or reorganization of the
Borrower, any Guarantor or otherwise.       26. Binding Effect; Several
Agreement; Assignments. Whenever in this Agreement any

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  of the parties hereto is referred to, such reference shall be deemed to
include the successors and assigns of such party; and all covenants, promises
and agreements by or on behalf of the Guarantors that are contained in this
Agreement shall bind and inure to the benefit of each party hereto and their
respective successors and assigns. This Agreement shall become effective as to
any Guarantor when a counterpart hereof executed on behalf of such Guarantor
shall have been delivered to the Collateral Agent, and a counterpart hereof
shall have been executed on behalf of the Collateral Agent, and thereafter shall
be binding upon such Guarantor and the Collateral Agent and their respective
successors and assigns, and shall inure to the benefit of such Guarantor, the
Collateral Agent and the other Secured Parties, and their respective successors
and assigns, except that no Guarantor shall have the right to a ssign its rights
or obligations hereunder or any interest herein (and any such attempted
assignment shall be void). In the event that a Guarantor ceases to be a
Subsidiary pursuant to a transaction permitted under the Loan Documents, such
Guarantor shall be released from its obligations under this Agreement without
further action. This Agreement shall be construed as a separate agreement with
respect to each Guarantor and may be amended, modified, supplemented, waived or
released with respect to any Guarantor without the approval of any other
Guarantor and without affecting the obligations of any other Guarantor
hereunder.        27. Waivers; Amendment. (a) No failure or delay of the
Collateral Agent in exercising any power or right hereunder shall operate as a
waiver thereof, nor shall any single or partial exercise of any such right or
power, or any abandonment or discontinuance of steps to enforce such a right or
power, preclude any other or further exercise thereof or the exercise of any
other right or power. The rights and remedies of the Collateral Agent hereunder
and of the other Secured Parties under the other Loan Documents are cumulative
and are not exclusive of any rights or remedies that they would otherwise have.
No waiver of any provision of this Agreement or consent to any departure by any
Guarantor therefrom shall in any event be effective unless the same shall be
permitted by paragraph (b) below, and then such waiver or consent shall be
effective only in the specific instance and for the purpose for which given. No
notice or demand on any Guarantor in any case shall entitle such Guarant or to
any other or further notice or demand in similar or other circumstances.      
(b)  Neither this Agreement nor any provision hereof may be waived, amended or
modified except pursuant to a written agreement entered into between the
Guarantors with respect to which such waiver, amendment or modification relates
and the Collateral Agent, subject to any consent required in accordance with
Section 11.02 of the Revolving Credit Agreement.       28. GOVERNING LAW. THIS
AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF
THE STATE OF NEW YORK.       29. Notices. All communications and notices
hereunder shall be in writing and given as provided in Section 11.01 of the
Revolving Credit Agreement. All communications and notices hereunder to each
Guarantor shall be given to it at its address or telecopy number set forth in
Schedule I, with a copy to the Borrower.       30. Survival of Agreement;
Severability. (a)  All covenants, agreements, representations and warranties
made by the Guarantors herein and in the certificates or other

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  instruments prepared or delivered in connection with or pursuant to this
Agreement or any other Loan Document shall be considered to have been relied
upon by the Collateral Agent and the other Secured Parties and shall survive the
making by the Lenders of the Loans regardless of any investigation made by the
Secured Parties or on their behalf, and shall continue in full force and effect
as long as the principal of or any accrued interest on any Loan or any other fee
or amount payable under this Agreement or any other Loan Document is outstanding
and unpaid and as long as the Commitments have not been terminated.       
(b)  In the event any one or more of the provisions contained in this Agreement
or in any other Loan Document should be held invalid, illegal or unenforceable
in any respect, the validity, legality and enforceability of the remaining
provisions contained herein and therein shall not in any way be affected or
impaired thereby (it being understood that the invalidity of a particular
provision in a particular jurisdiction shall not in and of itself affect the
validity of such provision in any other jurisdiction). The parties shall
endeavor in good-faith negotiations to replace the invalid, illegal or
unenforceable provisions with valid provisions the economic effect of which
comes as close as possible to that of the invalid, illegal or unenforceable
provisions.       31. Counterparts. This Agreement may be executed in
counterparts, each of which shall constitute an original, but all of which when
taken together shall constitute a single contract, and shall become effective as
provided in Section 3.04. Delivery of an executed signature page to this
Agreement by facsimile transmission shall be as effective as delivery of a
manually executed counterpart of this Agreement.       32. Rules of
Interpretation. The rules of interpretation specified in Section 1.02 of the
Revolving Credit Agreement shall be applicable to this Agreement.       33.
Jurisdiction; Consent to Service of Process. (a) Each Guarantor hereby
irrevocably and unconditionally submits, for itself and its property, to the
nonexclusive jurisdiction of any New York State court or Federal court of the
United States of America sitting in New York City, and any appellate court from
any thereof, in any action or proceeding arising out of or relating to this
Agreement or the other Loan Documents, or for recognition or enforcement of any
judgment, and each of the parties hereto hereby irrevocably and unconditionally
agrees that all claims in respect of any such action or proceeding may be heard
and determined in such New York State or, to the extent permitted by law, in
such Federal court. Each of the parties hereto agrees that a final judgment in
any such action or proceeding shall be conclusive and may be enforced in other
jurisdictions by suit on the judgment or in any other manner provided by law.
Nothing in this Agreement shall affect any righ t that the Collateral Agent or
any other Secured Party may otherwise have to bring any action or proceeding
relating to this Agreement or the other Loan Documents against any Guarantor or
its properties in the courts of any jurisdiction.       (b)  Each Guarantor
hereby irrevocably and unconditionally waives, to the fullest extent it may
legally and effectively do so, any objection that it may now or hereafter have
to the laying of venue of any suit, action or proceeding arising out of or
relating to this Agreement or the other Loan Documents in any New York State or
Federal court. Each of the parties hereto hereby irrevocably waives, to the
fullest extent permitted by law, the defense of an inconvenient forum to the
maintenance of such action or proceeding in any such court.

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  (c)  Each party to this Agreement irrevocably consents to service of process
in the manner provided for notices in Section 3.07. Nothing in this Agreement
will affect the right of any party to this Agreement to serve process in any
other manner permitted by law.       34. WAIVER OF JURY TRIAL. EACH PARTY HERETO
HEREBY WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY RIGHT IT
MAY HAVE TO A TRIAL BY JURY IN RESPECT OF ANY LITIGATION DIRECTLY OR INDIRECTLY
ARISING OUT OF, UNDER OR IN CONNECTION WITH THIS AGREEMENT OR THE OTHER LOAN
DOCUMENTS. EACH PARTY HERETO (A) CERTIFIES THAT NO REPRESENTATIVE, AGENT OR
ATTORNEY OF ANY OTHER PARTY HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THAT SUCH
OTHER PARTY WOULD NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE FOREGOING
WAIVER AND (B) ACKNOWLEDGES THAT IT AND THE OTHER PARTIES HERETO HAVE BEEN
INDUCED TO ENTER INTO THIS AGREEMENT AND THE OTHER LOAN DOCUMENTS, AS
APPLICABLE, BY, AMONG OTHER THINGS, THE MUTUAL WAIVERS AND CERTIFICATIONS IN
THIS SECTION 3.12.       35. Limitation on Guaranteed Amounts. Anything
contained in this Agreement to the contrary notwithstanding, the obligation of
each Guarantor hereunder shall be limited to a maximum aggregate amount equal to
the greatest amount that would not render such Guarantor's obligations hereunder
subject to avoidance as a fraudulent transfer or conveyance under Section 548 of
Title 11 of the United States Code or any provisions of applicable state law
(collectively, the "Fraudulent Transfer Laws"), in each case after giving effect
to all liabilities of such Guarantor, contingent or otherwise, that would be
taken into account in determining whether the incurrence of the obligation would
constitute a fraudulent conveyance under the Fraudulent Transfer Laws and after
giving effect, both in determining such Guarantor's probable debt hereunder and
in determining its assets, to the existence of any rights to subrogation,
contribution, reimbursement, indemnity or similar rights of such Gu arantor
pursuant to (a) applicable law or (b) any agreement, including the Indemnity,
Subrogation and Contribution Agreement.       36. Additional Guarantors.
Pursuant to Section 5.12 of the Revolving Credit Agreement, each Subsidiary Loan
Party that was not in existence or not a Subsidiary Loan Party on the date of
the Revolving Credit Agreement is required to enter into this Agreement as a
Guarantor upon becoming a Subsidiary Loan Party. Upon execution and delivery
after the date hereof by the Collateral Agent and such Subsidiary of an
instrument in the form of Annex 1, such Subsidiary shall become a Guarantor
hereunder with the same force and effect as if originally named as a Guarantor
herein. The execution and delivery of any instrument adding an additional
Guarantor as a party to this Agreement shall not require the consent of any
other Guarantor hereunder. The rights and obligations of each Guarantor
hereunder shall remain in full force and effect notwithstanding the addition of
any new Guarantor as a party to this Agreement.       37. Successor Guarantors.
Any Person may merge with any Guarantor in a transaction in which the surviving
entity is a Subsidiary of the Borrower; provided that if the surviving entity is
not the Guarantor, the surviving entity must be a corporation,

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  partnership or limited liability company organized and existing under the laws
of the United States of America, any State thereof or the District of Columbia,
and such surviving entity must expressly assume, by execution of appropriate
Loan Documents (or counterparts or supplements thereto), executed and delivered
to the Collateral Agent (in form reasonably satisfactory to the Collateral
Agent, as applicable) all the obligations of such Guarantor under this Guarantee
Agreement and the other applicable Loan Documents; and further provided that
prior to the consummation of such transaction, the Borrower must provide the
Collateral Agent with an officers' certificate and an opinion of counsel, each
stating that such consolidation, merger or transfer complies with the Loan
Documents.       38. Right of Setoff. If an Event of Default shall have occurred
and be continuing, each Secured Party is hereby authorized at any time and from
time to time, to the fullest extent permitted by law, to set off and apply any
and all deposits (general or special, time or demand, provisional or final) at
any time held and other Indebtedness at any time owing by such Secured Party to
or for the credit or the account of any Guarantor against any or all the
obligations of such Guarantor then existing under this Agreement and the other
Loan Documents held by such Secured Party, irrespective of whether or not such
Secured Party shall have made any demand under this Agreement or any other Loan
Document. The rights of each Secured Party under this Section 3.16 are in
addition to other rights and remedies (including any other rights of setoff)
which such Secured Party may have.       IN WITNESS WHEREOF, the parties hereto
have duly executed this Agreement as of the day and year first above written.

MEMC ELECTRONIC MATERIALS, INC.
By /s/ James M. Stolze
Name: James M. Stolze
Title:  Executive Vice President,
 Chief Financial Officer

By /s/ Kenneth L. Young
Name: Kenneth L. Young
Title:  Treasurer

By /s/ Kenneth L. Young
Name: Kenneth L. Young, in his capacity as Treasurer for each of the
Subsidiaries listed on Schedule I hereto

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  CITICORP USA, INC., as Administrative Agent and Collateral Agent

By: /s/ Allen Fisher
Name: Allen Fisher
Title: Vice President

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Schedule I to the
Guarantee Agreement

GUARANTORS

 

 

 

 

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Annex 1 to the
Guarantee Agreement

> > > > SUPPLEMENT NO. [ ] dated as of [ ], to the Guarantee Agreement dated as
> > > > of March 3, 2003 among MEMC ELECTRONIC MATERIALS, INC., a Delaware
> > > > corporation ("Borrower"), each of the subsidiaries listed on Schedule I
> > > > thereto (each such subsidiary, individually, a "Subsidiary" or a
> > > > "Guarantor" and, collectively, the "Subsidiaries" or "Guarantors") and
> > > > CITICORP USA, INC., as collateral agent (the "Collateral Agent") for the
> > > > Secured Parties (as defined in the Security Agreement).

A. Reference is made to the Revolving Credit Agreement dated as of December 5,
2002 (as amended, supplemented or otherwise modified from time to time, the
"Revolving Credit Agreement"), among the Borrower, the lenders from time to time
party thereto (the "Lenders"), the Collateral Agent and Citicorp USA, Inc., as
administrative agent for the Lenders (in such capacity, the "Administrative
Agent").

B. Capitalized terms used herein and not otherwise defined herein shall have the
meanings assigned to such terms in the Guarantee Agreement and the Revolving
Credit Agreement.

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C. The Guarantors have entered into the Guarantee Agreement in order to induce
the Lenders to make Loans. Pursuant to Section 5.12 of the Revolving Credit
Agreement, each Subsidiary Loan Party that was not in existence or not a
Subsidiary Loan Party on the date of the Revolving Credit Agreement is required
to enter into the Guarantee Agreement as a Guarantor upon becoming a Subsidiary
Loan Party. Section 3.14 of the Guarantee Agreement provides that additional
Subsidiaries may become Guarantors under the Guarantee Agreement by execution
and delivery of an instrument in the form of this Supplement. The undersigned
Subsidiary (the "New Guarantor") is executing this Supplement in accordance with
the requirements of the Revolving Credit Agreement to become a Guarantor under
the Guarantee Agreement in order to induce the Lenders to make additional Loans
and as consideration for Loans previously made.

Accordingly, the Collateral Agent and the New Guarantor agree as follows:

SECTION 1. In accordance with Section 3.14 of the Guarantee Agreement, the New
Guarantor by its signature below becomes a Guarantor under the Guarantee
Agreement with the same force and effect as if originally named therein as a
Guarantor and the New Guarantor hereby (a) agrees to all the terms and
provisions of the Guarantee Agreement applicable to it as a Guarantor thereunder
and (b) represents and warrants that the representations and warranties made by
it as a Guarantor thereunder are true and correct on and as of the date hereof
except to the extent a representation and warranty expressly relates solely to a
specific date in which case such representation and warranty shall be true and
correct on such date. Each reference to a "Guarantor" in the Guarantee Agreement
shall be deemed to include the New Guarantor. The Guarantee Agreement is hereby
incorporated herein by reference.

SECTION 2. The New Guarantor represents and warrants to the Collateral Agent and
the other Secured Parties that this Supplement has been duly authorized,
executed and delivered by it and constitutes its legal, valid and binding
obligation, enforceable against it in accordance with its terms.

SECTION 3. This Supplement may be executed in counterparts, each of which shall
constitute an original, but all of which when taken together shall constitute a
single contract. This Supplement shall become effective when the Collateral
Agent shall have received counterparts of this Supplement that, when taken
together, bear the signatures of the New Guarantor and the Collateral Agent.
Delivery of an executed signature page to this Supplement by facsimile
transmission shall be as effective as delivery of a manually executed
counterpart of this Supplement.

SECTION 4. Except as expressly supplemented hereby, the Guarantee Agreement
shall remain in full force and effect.

SECTION 5. THIS SUPPLEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE
WITH, THE LAWS OF THE STATE OF NEW YORK.

SECTION 6. In case any one or more of the provisions contained in this
Supplement should be held invalid, illegal or unenforceable in any respect, the
validity, legality and enforceability of the remaining provisions contained
herein and in the Guarantee Agreement shall not in any way be affected or
impaired thereby (it being understood that the invalidity of a particular
provision hereof in a particular jurisdiction shall not in and of itself affect
the validity of such provision in any other jurisdiction). The parties hereto
shall endeavor in good-faith negotiations to replace the invalid, illegal or
unenforceable provisions with valid provisions the economic effect of which
comes as close as possible to that of the invalid, illegal or unenforceable
provisions.

SECTION 7. All communications and notices hereunder shall be in writing and
given as provided in Section 3.07 of the Guarantee Agreement. All communications
and notices hereunder to the New

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Guarantor shall be given to it at the address set forth under its signature
below, with a copy to the Borrower.

SECTION 8. The New Guarantor agrees to reimburse the Collateral Agent for its
out-of-pocket expenses in connection with this Supplement, including the
reasonable fees, disbursements and other charges of counsel for the Collateral
Agent.

IN WITNESS WHEREOF, the New Guarantor and the Collateral Agent have duly
executed this Supplement to the Guarantee Agreement as of the day and year first
above written.

[NAME OF NEW GUARANTOR], By________________________________ 
Name:
Title:
Address:
CITICORP USA, INC., as Collateral Agent, By________________________________ 
Name:
Title:
Address:

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