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                                                               EXHIBIT 10-FFF(1)
                   FIRST AMENDMENT TO OVERNIGHT LOAN AGREEMENT

     This First  Amendment to Overnight  Loan Agreement  ("First  Amendment") is
effective as of September 1, 1998  between MEMC  ELECTRONIC  MATERIALS,  INC., a
Delaware corporation, as the Borrower (the "Borrower"),  and Huls Corporation, a
company formed under the laws of the State of Delaware, U.S.A. ("Huls").

                                    Recitals

     WHEREAS,  Borrower and Huls entered into an Overnight Loan Agreement  dated
as of October 31, 1997 (the "Loan  Agreement")  pursuant to which Huls agreed to
extend up to US$10,000,000 of credit to Borrower on a day to day basis;

     WHEREAS,  Borrower,  Huls and  certain  affiliates  of Huls have  agreed to
extend additional  credit to Borrower and to restructure the existing  financing
provided by Huls and its affiliates to Borrower, and

     WHEREAS, as part of such restructuring,  Borrower and Huls desire to change
the interest  rate  payable by Borrower to Huls and the maturity  date under the
Loan Agreement.

     NOW THEREFORE,  in consideration  of the foregoing  premises and the mutual
covenants and conditions hereinafter set forth, the parties agree as follows:

     1. Amendment. Sections 1 through 9 of the Loan Agreement are hereby amended
and  restated  in their  entirety  as set forth in ANNEX A  attached  hereto and
incorporated by reference herein.

     2.  Counterparts.  This First  Amendment  may be  executed in any number of
counterparts and by different parties hereto in separate  counterparts,  each of
which  when so  executed  shall be deemed  an  original  and all of which  taken
together shall  constitute one and the same agreement.  Delivery of any executed
counterpart of a signature page to this First  Amendment by telecopier  shall be
effective  as  delivery  of  a  manually  executed  counterpart  of  this  First
Amendment.

     3. Governing Law. This First  Amendment shall be governed by, and construed
in accordance with, the laws of the State of New York.

     IN  WITNESS  WHEREOF,  the parties hereto have caused this First  Amendment
to  be  executed  by  their duly authorized representatives effective as of  the
day and year first above written.


MEMC ELECTRONIC MATERIALS, INC., as Borrower


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


HULS CORPORATION


By: /s/ H. J. Biangardi
    ---------------------------------
      Name:  H. J. Biangardi
      Title: President and CEO


By: /s/ John Schaffner
    ---------------------------------
      Name:  John Schaffner for Mitchell Solomowitz
      Title: Treasurer

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                                                                         Annex A
                                                              To First Amendment

1.   Definitions:  The  following  capitalized  terms used herein shall have the
     following meanings:

          "Agreement" means this Overnight Loan Agreement.

          "Applicable  Spread" means a percentage  per annum equal to the excess
     of (a) the Bloomberg  fair market  sector  curves  (adjusted for the chosen
     interest rate method) applicable two business days prior to October 1, 1998
     to a B3 rated  industrial  borrower  for the  period  from  October 1, 1998
     through  October  31,  2001 over (b) the  corresponding  Swap Rate for such
     period.

          "Borrower" or "MEMC" means MEMC Electronic Materials, Inc.

          "Extension  Maturity  Date",  if  any,  means  either  (i)  the  first
     anniversary  of October 30, 1999,  or (ii) if there has been an  applicable
     Extension  Maturity  Date on or prior  to  December  31,  2000,  the  first
     anniversary of such prior  Extension  Maturity Date;  provided,  that in no
     event shall an Extension Maturity Date be after December 31, 2001.

          "Final  Maturity Date" means October 30, 1999 or, if  applicable,  the
     Extension Maturity Date.

          "Huls" means Huls Corporation.

          "Interest Rate" shall be the rate determined under Section 5.

          "Lender"  means  Huls or any  Eligible  Assignee  (as  defined  in the
     Reference  Agreement) to whom Huls (or any  successor  Lender) has assigned
     its rights and obligations pursuant to Section 11.

          "Person" means an individual,  partnership,  corporation  (including a
     business trust), joint stock company,  trust,  unincorporated  association,
     joint venture,  limited  liability company or other entity, or a government
     or any political subdivision or agency thereof.

          "Reference  Agreement"  means that certain Credit Agreement dated June
     26, 1997 in the amount of  US$50,000,000  between Borrower and Huls, as the
     same may be amended from time to time.

          "Replacement Financing Arrangement" means a financing arrangement with
     any  Person  who is not an  affiliate  of the  Borrower  or the  Lender  on
     substantially  the terms which would apply hereunder during the period from
     the then applicable  Final Maturity Date to the latest  possible  Extension
     Maturity  Date,  provided  that  the  interest  rate  of  such  Replacement
     Financing  Arrangement shall be no higher than the Interest Rate and, if no
     lesser interest rate is available, shall be the Interest Rate.

2.   Principal and Value. From time to time,  beginning October 31, 1997, Lender
     agrees to lend to Borrower and Borrower agrees to borrow from the Lender an
     amount  to  be  designated  by  Borrower,   not  to  exceed  $10,000,000.00
     outstanding at any one time (each such borrowing,  an "Advance").  The loan
     shall  be  evidenced  by a  promissory  note in  substantially  the form of
     Exhibit "A"  attached  hereto.  All loans and  repayments  shall be made by
     Borrower by drawing funds from or depositing funds in Borrower's account at
     Citibank  N.A.,  New York,  New York that will zero balance with the Huls's
     account at Citibank  N.A.,  New York,  New York (Account No.  4070-0001) or
     such  other  account  of  the  Lender  as  it  may  designate  ("designated
     account").

3.   Term and Maturity.  (a) Final Maturity  Date.  The principal  amount of the
     loan  outstanding  together with any interest due and outstanding  shall be
     paid by Borrower to the Lender on the Final Maturity Date, or at such later
     date as may be mutually agreed in writing by the parties.

          (b) Extension. If the then applicable Final Maturity Date is a date on
     or before  December  31, 2000 and the  Borrower  may desire that the Lender
     extend the then  applicable  Final Maturity Date to the Extension  Maturity
     Date,  then (a) the Borrower  shall give  written  notice of said fact (the
     "Extension  Request  Notice")  to the  Lender no later than four (4) months
     before the Final Maturity Date, (b) the Borrower shall use its best efforts
     to obtain and enter into on or before the date which is two months prior to
     the Final Maturity Date a Replacement  Financing Arrangement and (c) if the
     Borrower shall not have entered into a Replacement Financing Arrangement on
     or before the date which is two months  prior to the Final  Maturity  Date,
     the Borrower shall deliver to the Lender a certificate of the Borrower (the
     "Extension  Certificate")  (x) certifying that the Borrower has not entered
     into a Replacement  Financing  Arrangement,  but the Borrower used its best
     efforts to do so as required by clause (b) and setting  forth such evidence
     and back-up detail as necessary to demonstrate the efforts made,  including
     a  written  letter  from  each  bank  from  which a  Replacement  Financing
     Arrangement  as  required  by clause  (b) was  requested,  indicating  that
     Borrower  made such a request  and that the  request  was  denied,  and (y)
     requesting  that the  Final  Maturity  Date be  extended  to the  Extension
     Maturity Date.  For purposes of this Section,  the Borrower shall be deemed
    

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     to have  complied  with  the  requirement  to use  its  "best  efforts"  by
     requesting  from and, if applicable,  diligently  negotiating a Replacement
     Financing  Arrangement  as  required  by clause  (b) with each of three (3)
     commercial  banks that are  nationally  recognized in the United States and
     each have total assets in excess of $20,000,000,000.  Lender shall have the
     right to  designate,  within ten (10)  Business  Days  after  receipt of an
     Extension  Request  Notice,  one  of the  three  banks  referred  to in the
     preceding  sentence.  For purposes of this  Section,  diligent  negotiation
     shall mean  negotiation  in good faith and without  denial or  unreasonable
     delay of any  reasonable  request  by any  such  bank  for  information  in
     connection  with its  consideration  of providing a  Replacement  Financing
     Arrangement  to Borrower.  For the  avoidance of doubt,  nothing  herein is
     intended  to  prevent  Borrower  from  obtaining  a  Replacement  Financing
     Arrangement on terms equal to or better than those provided hereunder.

          Following receipt of the Extension Certificate,  the Lender shall have
     the right  (without any  obligation  to do so) to obtain for the Borrower a
     Replacement  Financing  Arrangement  on terms equal to or better than those
     provided hereunder.

          If the Borrower has (a) delivered the Extension  Request Notice within
     the time period  specified  above,  (b) used its best efforts to obtain and
     enter into a Replacement  Financing Arrangement and delivered the Extension
     Certificate within the time period specified above and (c) not unreasonably
     or in bad faith refused to enter into a Replacement  Financing  Arrangement
     (with terms equal to or better than those provided  hereunder) obtained for
     the Borrower by the Lender pursuant to the preceding  paragraph,  the Final
     Maturity  Date shall be extended  to the  Extension  Maturity  Date and the
     interest  rate shall be the Interest  Rate.  The Lender  shall  provide the
     Borrower with a written notice setting forth the Interest Rate.

          The Borrower  shall be  responsible  for the payment of any  customary
     commitment  fee and other fees in connection  with  obtaining a Replacement
     Financing Arrangement.

          For the  avoidance of doubt,  in no event shall an Extension  Maturity
     Date be requested by the Borrower  after  December 31, 2000 or be on a date
     after December 31, 2001.

4.   Rollover  Dates.  Any amount  borrowed  hereunder  shall be on the basis of
     daily  rollover  periods.  Each rollover date shall be a banking day in New
     York,  New York  ("banking  day").  However,  should  the  designated  bank
     designated  by the  Lender in  Section 2 be  closed on a banking  day,  the
     Lender would not be required to loan money to Borrower  nor would  Borrower
     have  the  option  to repay a loan.  On the  initial  and  each  respective
     rollover date thereafter,  Borrower shall have the option to repay the full
     principal  amount  outstanding or any portion  thereof,  rollover an amount
     outstanding,  or  borrow  an  additional  amount  provided  that the  total
     principal  amount  will not exceed  $10,000,000.00.  Borrower  will  notify
     Lender of  repayments,  draw-downs and rollovers by a telefax or memorandum
     from Borrower,  to Lender by 10:00 a.m. Central time on the day money is to
     be borrowed, or repaid.

5.   Interest Rates.  Until September 30, 1998,  interest shall be calculated at
     the FED Funds  opening  rate plus  .25% as quoted by VEBA  Corporation  and
     supplied  by  Citibank.  On and after  October 1, 1998,  interest  shall be
     calculated  daily at the FED Funds opening rate plus the Applicable  Spread
     as  quoted  by  VEBA  Corporation  and  supplied  by  Citibank.  For  loans
     outstanding  on days  other  than  banking  days,  the  interest  shall  be
     calculated at the rate  applicable for the last preceding  banking day. The
     interest  rate  shall be  furnished  daily if there is a loan  outstanding.
     Interest  shall accrue on all  outstanding  amounts and shall be calculated
     based upon a 360 day year.

6.   Payment of Interest.  Payments of interest  shall be made by wire transfer,
     or other method of same day  settlement,  only on banking  days,  not later
     than 10:00 a.m.  Central time, to the account of Huls,  with Citibank N.A.,
     New York, New York, (Account No. 4070-0001) or to such other account of the
     Lender as it may designate.  Interest will be payable monthly, with payment
     due the day after the Lender  notifies  Borrower  of the amount due for the
     prior month.

7.   Penalty.  If Borrower shall borrow,  repay or rollover an amount  different
     than which it notifies the Lenders  pursuant to paragraph 4, Borrower shall
     pay to the  Lender  a  penalty  equal  to the  .25%  of the  amount  of the
     understatement divided by 360.

8.   Covenants.  So long as any Advance shall remain unpaid or Lender shall have
     any  Commitment  hereunder,  the Borrower will comply with the  Affirmative
     Covenants  set forth in  Section  5.01 (on and after the  Change of Control
     Date as defined in the  Reference  Agreement)  and the  Negative  Covenants
     (including  Negative  Pledge)  set forth in Section  5.02 of the  Reference
     Agreement, all of which the Borrower, by signing this Agreement,  expressly
     repeats and incorporates herein.

9.   Conditions Precedent to each Borrowing. The obligation of Lender to make an
     Advance on the occasion of each borrowing shall be subject to the condition
     precedent  that no event has  occurred and is  continuing,  or would result
     from such Advance or from the application of the proceeds  therefrom,  that

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     constitutes a Default under the Reference Agreement.

10.  Events of Default.  Each of the Events of Default set forth in Section 6.01
     of the Reference  Agreement shall constitute an Event of Default  hereunder
     and the Lender  shall have the rights with respect to Events of Default and
     Defaults with respect to the amounts loaned hereunder that are set forth in
     the Reference Agreement.

11.  Assignment.  Lender  may  assign  its  rights  and  obligations  under this
     Agreement in whole but not in part and otherwise in accordance with Section
     8.07 of the Reference Agreement, provided that any such assignment shall be
     made to a single Eligible Assignee (as defined in the Reference Agreement).

12.  Commitment  Fee. The Borrower  agrees to pay to the Lender a commitment fee
     on the unused  portion of Lender's  commitment  from October 1, 1998 in the
     case of Huls and from the effective  date  specified in the  Assignment and
     Acceptance  pursuant  to which it  became  a Lender  in case of each  other
     Lender  until the Final  Maturity  Date at a rate per annum equal to 1/4 of
     1%,  payable  monthly,  with payment due the day after the Lender  notifies
     Borrower of the amount due for the prior month.

13.  Governing  Law.  This  Agreement  shall be governed  by, and  construed  in
     accordance with, the laws of the State of New York.