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                                                                 EXHIBIT 10.33


                              ETEC SYSTEMS, INC.
                            26460 Corporate Avenue
                           Hayward, California 94545


                                August 7, 1996

ESI (CA) QRS 12-6, Inc.
c/o W.P. Carey & Co., Inc.
50 Rockefeller Plaza 
New York, New York 10020 

Attention:  Mr. Barclay Jones, 

Creditanstalt Corporate Finance, Inc.
4 Embarcadero Center, Suite 1630
San Francisco, California

Attention:  Mr. Jack Bertges

Ladies and Gentlemen:     

     Whereby, in furtherance of and in connection with the modification of
certain registration rights held by ESI (CA) QRS12-6, Inc. ("Landlord") pursuant
to that certain Warrant Agreement dated as of February 1, 1995 by and between
Landlord and Etec Systems, Inc. (the "Company"), Landlord and the Company have
agreed to (1) amend the Warrant Agreement, and (2) refund a portion of the
purchase price of the Leased Premises (as defined in the Lease Agreement (the
"Lease") dated as of February 1, 1995 by and between Landlord and the Company).
This letter will constitute our agreement in accordance with the following
terms:

     1.   Landlord is presently the holder of 159,314 warrants (the "Warrants")
to purchase Common Stock, par value $.01 per share ("Common Stock") of the
Company, and Creditanstalt Corporate Finance, Inc. ("Creditanstalt") is
presently the holder of 53,104 Warrants.  The Warrants are held subject to
the terms of the Warrant Agreement.

     2.   To effect the purposes of Section 32 of the Warrant Agreement it is
hereby agreed that Landlord shall retain 68,768 Warrants (the "Retained
Warrants") and Creditanstalt shall receive 22,461 shares of Common Stock (the
"Retained Stock").

     3.   The Warrant Agreement is hereby amended to permit the holders to
exercise the Warrants either (a) by paying the cash exercise price or (b) in a
cashless exercise, pursuant to which the holder of the Warrants would receive
the full number of shares of stock, less that number of shares having a fair
market 

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value (determined at the time of exercise) equal to the aggregate
exercise price.

     4.   Concurrently with execution and delivery hereof, the Company shall
refund to Landlord $2,633,473 ("Refund Amount") as a reduction of Landlord's
purchase price. The Refund Amount shall be used to make prepayment to
Creditanstalt as a principal prepayment in respect of the indebtedness of
Landlord evidenced by that certain Real Estate note (the "Note") dated February 
1,1995 in the original principal amount of $6,250,000. Effective as of the first
Basic Rent Payment Date after such prepayment, the scheduled monthly payments
due under the Note shall be equal to $33,551 monthly Basic Rent under the Lease
shall be reduced to $85,253, and, effective immediately, the schedule of
Termination Values attached to the Lease as Schedule 1 for each Lease Year be
reduced by an amount equal to $1,316,736.

     5.   The foregoing transactions satisfy the rights and obligations of the
parties under Section 32 of the Warrant Agreement, and the Landlord shall
thereafter hold the Retained Warrants and Creditanstalt shall thereafter hold
the Retained Stock free of any rights of the Company under such Section.

     6.   The Company hereby acknowledges and agrees that the foregoing
amendment and exercise of Warrants is made in furtherance of the Company's
obligations under the Warrant Agreement and no additional consideration is being
received by the Company in connection herewith.

     7.   Terms not otherwise defined herein are as defined in the Lease.  

     If the foregoing is acceptable, please sign a copy of this letter and
return it to us.

                                  Very truly yours,

                                  ETEC SYSTEMS, INC.



                                  By  /s/ Melanie Mock
                                    -------------------------
                                          Melanie Mock
                                           Treasurer



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     We consent and agree as set forth above.  

                                       ESI (CA) QRS 12-6, INC.



                                       By /s/ Gordon J. Whiting
                                          --------------------------------
                                       Name   Gordon J. Whiting                
                                            ------------------------------
                                       Title  Vice President         
                                             -----------------------------
                                                       

                                       CREDITANSTALT CORPORATE FINANCE, INC.


                                       By /s/ Jack R. Bertges
                                          --------------------------------
                                       Name   Jack R. Bertges
                                             -----------------------------
                                       Title  Senior Vice President  
                                             -----------------------------


                                       By /s/ James F. McCann
                                          --------------------------------
                                       Name   James F. McCann
                                             -----------------------------
                                       Title  Vice President
                                             -----------------------------

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