Exhibit 10-xxx(6)

AMENDMENT NO. 1 TO THE AMENDED AND RESTATED PLEDGE AGREEMENT

AMENDMENT NO. 1, dated as of March 3, 2003 (this "Amendment No. 1"), to the
Amended and Restated Pledge Agreement, dated as of December 21, 2001 (as
amended, supplemented or otherwise modified from time to time, the "Pledge
Agreement"), among MEMC Electronic Materials, Inc., a Delaware corporation (the
"Borrower"), each subsidiary of the Borrower party thereto (each such subsidiary
individually a "Subsidiary Pledgor" and, collectively, the "Subsidiary
Pledgors"; and the Subsidiary Pledgors and Borrower are referred to collectively
herein as the "Pledgors") and Citicorp USA, Inc., as collateral agent (in such
capacity, the "Collateral Agent") for the Secured Parties.

W I T N E S S E T H:

WHEREAS, the Borrower entered into a revolving credit agreement, dated as of
December 21, 2001, among the Borrower, the lenders party thereto and Citicorp
USA, Inc. as administrative agent and collateral agent (as amended, supplemented
or otherwise modified from time to time, the "Bank Revolving Credit Agreement"),
and contemporaneously therewith, the Fund Guarantors entered into the Guaranty,
pursuant to which the Fund Guarantors guaranteed the obligations of the Borrower
under the Bank Revolving Credit Agreement;

WHEREAS, pursuant to the Pledge Agreement, the Pledgors agreed to pledge and
grant to the Collateral Agent a security interest in the Collateral for the
ratable benefit of the Secured Parties under a reimbursement agreement, dated as
of December 21, 2001, among the Borrower, the Fund Guarantors and Citicorp USA,
Inc. as administrative agent and collateral agent (as amended, supplemented or
otherwise modified from time to time, the "Reimbursement Agreement"), pursuant
to which the Borrower agreed to reimburse the Fund Guarantors for any and all
payments made by the Fund Guarantors under the Guaranty;

WHEREAS, the Borrower has entered into that certain revolving credit agreement,
dated as of December 5, 2002, with the lenders party thereto (the "Investor
Lenders") and Citicorp USA, Inc. as administrative agent and collateral agent
(as amended, supplemented or otherwise modified from time to time, the "Investor
Revolving Credit Agreement"), pursuant to which the Investor Lenders agreed to
provide the Borrower with a revolving credit facility in an aggregate principal
amount not to exceed $35,000,000;

WHEREAS, to induce the Investor Lenders to enter into the Investor Revolving
Credit Agreement, the Pledgors agreed to pledge and grant a senior subordinated
security interest in the Collateral (the "Investor Security Interest") to secure
the Borrower's obligations under the Investor Revolving Credit Agreement for the
ratable benefit of the Secured Parties (as defined in the Investor Revolving
Credit Agreement), pursuant to the Security Documents (as defined in the
Investor Revolving Credit Agreement);

WHEREAS, the Pledgors and the Collateral Agent wish to amend the Pledge
Agreement to, among other things, account for Investor Security Interest;

WHEREAS, pursuant to Section 10 of the Pledge Agreement, the Pledge Agreement
may be amended or modified pursuant to a written agreement among the Collateral
Agent and the Pledgors with respect to which such amendment or modification is
to apply, subject to any consent required in accordance with Section 8.09 of the
Reimbursement Agreement; and

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

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1. Defined Terms. Unless otherwise defined herein or amended hereby, capitalized
terms used herein which are defined in the Pledge Agreement or the Reimbursement
Agreement are used herein as therein defined.

2. Amendments to the Pledge Agreement.

(a) Section 3(b) is hereby amended to read in its entirety as follows (added
language in bold type):

(b) except for the lien and security interest granted under the Revolving Credit
Loan Documentation (the "Revolver Security Interest") as security for the
payment or performance, as the case may be, in full of the Revolving Credit
Obligations (as defined in the Revolving Credit Loan Documentation), the lien
and security interest granted under the Investor Revolving Credit Documentation
(as defined in the Security Agreement, as amended) for the payment or
performance, as the case may be, of the Investor Revolver Obligations (as
defined in the Security Agreement, as amended), the lien and security interest
granted under the Indenture Documentation as security for the payment or
performance, as the case may be, of the Indenture Obligations, and the security
interest granted hereunder, such Pledgor (i) is and will at all times continue
to be the direct owner, beneficially and of record, of the Pledged Securities
indicated on Schedule II, (ii) holds the same free and clear of all Liens, (iii)
will make no assignment, pledge, hypothecation or transfer of, or create or
permit to exist any security interest in or other Lien on, the Collateral, other
than pursuant hereto, and (iv) subject to Section 5, will cause any and all
Collateral, whether for value paid by such Pledgor or otherwise, to be forthwith
deposited with the Collateral Agent and pledged or assigned hereunder;

(b) Section 3(c) is hereby amended to read in its entirety as follows (added
language in bold type):

(c) such Pledgor (i) has the power and authority to pledge the Collateral in the
manner hereby done or contemplated and (ii) will defend its title or interest
thereto or therein against any and all Liens (other than the Liens created by
this Agreement, the Revolving Credit Loan Documentation, the Investor Revolving
Credit Documentation or the Indenture Documentation), however arising, of all
Persons whomsoever;

(c) Section 3(e) is hereby amended to add the following parenthesis at the end
of Section 3(e) and after the words "Reimbursement Obligations": "(subject only
to the lien and security interest that comprise the Revolver Security
Interest)".

(d) Section 7 is hereby amended as follows:

(i) immediately after the paragraph beginning with "SECOND, to the payment in
full of the Reimbursement Obligations . . ." and before the paragraph beginning
with "THIRD, to the payment in full of the Indenture Obligations outstanding . .
.", the following paragraph is inserted: "THIRD, to the payment in full of the
Investor Revolver Obligations outstanding;";

(ii) the word "THIRD" in the paragraph beginning with "THIRD, to the payment in
full of the Indenture Obligations outstanding . . ." is deleted and replaced
with the word: "FOURTH"; and

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(iii) the word "FOURTH" in the paragraph beginning with "FOURTH, to the Pledgors
. . ." is deleted and replaced with the word: "FIFTH".

3. Effectiveness. This Amendment No. 1 shall become effective as of the date
first written above (the "First Amendment Effective Date").

4. Reference to and Effect on the Pledge Agreement.

(a) On or after the First Amendment Effective Date, each reference in the Pledge
Agreement to "this Agreement," "hereunder," "hereof," "herein," or words of like
import referring to the Pledge Agreement, shall mean and be a reference to the
Pledge Agreement, as amended by this Amendment No. 1.

(b) Except as amended hereby, the provisions of the Pledge Agreement are and
shall remain in full force and effect.

(c) This Amendment No. 1 shall not be construed as a waiver or consent to any
further or future action on the part of any of the Pledgors that would require a
waiver or consent of the Collateral Agent.

5. Counterparts. This Amendment No. 1 may be executed in counterparts and all of
the said counterparts taken together shall be deemed to constitute one and the
same instrument.

6. GOVERNING LAW. THIS AMENDMENT NO. 1 SHALL BE GOVERNED BY, AND CONSTRUED AND
INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

IN WITNESS WHEREOF, the Borrower, each of the Subsidiary Pledgors, the
Collateral Agent and the Fund Guarantors have caused this Amendment No. 1 to be
executed and delivered by their duly authorized officers as of the date first
above written.

MEMC ELECTRONIC MATERIALS, INC.,

By: /s/ Kenneth L. Young
Name: Kenneth L. Young
Title: Treasurer EACH OF THE SUBSIDIARY PLEDGORS MEMC ELECTRONIC MATERIALS,
INC.,

By: /s/ Kenneth L. Young
Name: Kenneth L. Young, in his capacity as Treasurer for each of the Subsidiary
Pledgors CITICORP USA, INC. as Collateral Agent

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

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    Name of Institution:

TPG PARTNERS III, L.P.

By:TPG GenPar III, L.P.,
Its General Partner

By:TPG Advisors III, Inc.,
Its General Partner

By: /s/ Richard A. Ekleberry
Name:Richard A. Ekleberry
Title:Vice President Name of Institution:

TPG PARALLEL III, L.P.

By:TPG GenPar III, L.P.,
Its General Partner

By:TPG Advisors III, Inc.,
Its General Partner

By: /s/ Richard A. Ekleberry
Name:Richard A. Ekleberry
Title:Vice President     Name of Institution:

TPG INVESTORS III, L.P.

By:TPG GenPar III, L.P.,
Its General Partner

By:TPG Advisors III, Inc.,
Its General Partner

By: /s/ Richard A. Ekleberry
Name:Richard A. Ekleberry
Title:Vice President Name of Institution:

FOF PARTNERS III, L.P.

By:TPG GenPar III, L.P.,
Its General Partner

By:TPG Advisors III, Inc.,
Its General Partner

By: /s/ Richard A. Ekleberry
Name:Richard A. Ekleberry
Title:Vice President

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Name of Institution:

FOF PARTNERS III-B, L.P.

By:TPG GenPar III, L.P.,
Its General Partner

By:TPG Advisors III, Inc.,
Its General Partner

By: /s/ Richard A. Ekleberry
Name:Richard A. Ekleberry
Title:Vice President     Name of Institution:

TPG DUTCH PARALLEL III, C.V.

By:TPG GenPar Dutch, L.L.C.,
Its General Partner

By: TPG GenPar III, L.P.,
Its Sole Member

By:TPG Advisors III, Inc.,
Its General Partner

By: /s/ Richard A. Ekleberry
Name:Richard A. Ekleberry
Title:Vice President Name of Institution:

T3 PARTNERS, L.P.

By:T3 GenPar, L.P.,
Its General Partner

By:T3 Advisors, Inc.,
Its General Partner

By: /s/ Richard A. Ekleberry
Name:Richard A. Ekleberry
Title:Vice President

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    Name of Institution:

T3 PARALLEL, L.P.

By:T3 GenPar, L.P.,
Its General Partner

By:T3Advisors, Inc.,
Its General Partner

By: /s/ Richard A. Ekleberry
Name:Richard A. Ekleberry
Title:Vice President Name of Institution:

T3 INVESTORS, L.P.

By:T3 GenPar, L.P.,
Its General Partner

By:T3 Advisors, Inc.,
Its General Partner

By: /s/ Richard A. Ekleberry
Name:Richard A. Ekleberry
Title:Vice President Name of Institution:

T3 DUTCH PARALLEL, C.V.

By:T3 GenPar Dutch, L.L.C.,
Its General Partner

By:T3 GenPar, L.P.,
Its Sole Member

By:T3 Advisors, Inc.,
Its General Partner

By: /s/ Richard A. Ekleberry
Name:Richard A. Ekleberry
Title:Vice President     Name of Institution:

T3 PARTNERS II, L.P.

By:T GenPar II, L.P.,
Its General Partner

By:T3 Advisors II, Inc.,
Its General Partner

By: /s/ Richard A. Ekleberry
Name:Richard A. Ekleberry
Title:Vice President

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Name of Institution:

T3 PARALLEL II, L.P.

By:T3 GenPar II, L.P.,
Its General Partner

By:T3 Advisors II, Inc.,
Its General Partner

By: /s/ Richard A. Ekleberry
Name:Richard A. Ekleberry
Title:Vice President Title: Name of Institution:

GREEN EQUITY INVESTORS III, L.P.

By: GEI Capital III, LLC, as its General Partner

By: /s/ John Danhakl
Name: John Danhakl
Title:     Name of Institution:

GREEN EQUITY INVESTORS SIDE III, L.P.

By: GEI Capital III, LLC, as its General Partner

By: /s/ John Danhakl
Name: John Danhakl
Title:

Name of Institution: TCW/CRESCENT MEZZANINE PARTNERS III, L.P.,
TCW/CRESCENT MEZZANINE TRUST III and
TCW/CRESCENT MEZZANINE PARTNERS III NETHERLANDS, L.P.

By: TCW/Crescent Mezzanine Management III, L.L.C.,
as Its Investment Manager

By: TCW Asset Management Company, as Its Sub-Advisor

By: /s/ Jean-Marc Chapus
Name: Jean-Marc Chapus
Title: Group Managing Director

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