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                                  EXHIBIT 10.15

April 20, 1999


Mr. Bruce R. Wright
47 Red Birch Court
Danville, CA 94506



Dear Bruce:


It is my pleasure to offer you a position with Ultratech Stepper, Inc., based on
the following:

TITLE:                       Senior Vice President and Chief Financial Officer

SALARY:                      $225,000 per year

HIRE-ON BONUS:               $25,000.00 payable in our first normal pay period

PAID-TIME OFF:               11 HOLIDAYS PER YEAR (See Schedule), plus
                             vacation accrued at the rate of 2.30 hours per week
                             for the 1st year. Ultratech Stepper also observes
                             mandatory unpaid shutdowns (See attached
                             Holiday/Shutdown Schedule).

STOCK OPTIONS:               100,000 SHARES. As part of your terms of
                             employment, you would be eligible to receive
                             Ultratech Stepper, Inc. stock options as granted
                             to all employees. The price of your options will
                             be the closing price on the day your options are
                             approved by the Compensation Committee.

                             50,000 SHARES AT THE COMPLETION OF ONE YEAR OF
                             SERVICE. You will receive this grant of Ultratech
                             Stepper, Inc. stock options at the completion of
                             your first year of service. The price of your
                             options will be the closing price of our stock on
                             the first day of your second year of service.

EXECUTIVE COMP:              In the event of an involuntary termination
                             within your first year of employment you will
                             receive your base salary paid bi-weekly for six
                             months from the date you are separated. In addition
                             your stock options will continue to vest for three
                             hundred sixty-six (366) days from your start date.

START DATE:                  6/1/99

REPORT TO:                   Arthur W. Zafiropoulo

This offer of employment is contingent upon your completion of a background
check and a pre-employment physical/drug screen test, which will be scheduled.


Please understand that this offer does not constitute a GUARANTEE of continued
employment for any particular period, and that your relationship with Ultratech
Stepper, Inc., is an "at will" relationship and is subject to termination by
either party at any time, for any reason, without cause or notice.


Only the Chief Executive Officer of Ultratech Stepper, Inc., has the authority
to alter the "at will" nature of your employment status, and any such change in
status may be effected only by an expressed written employment contract signed
by the Chief Executive Officer of Ultratech Stepper, Inc.


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Your acceptance of this employment offer with Ultratech Stepper, Inc., is
contingent upon your agreement that any future disputes with Ultratech Stepper,
Inc., regarding termination of your employment will be resolved solely and
exclusively in accordance with the enclosed Employment Agreement. By accepting
this offer of employment, you further agree that any decision issued by an
arbitrator pursuant to the referenced procedure will be final and binding upon
Ultratech Stepper, Inc., and you.


Finally, your employment with Ultratech Stepper, Inc is contingent upon your
execution of the enclosed Employment Agreement. Please complete this form and
return it to Human Resources with your signed acceptance of this letter. The
Human Resources Department will contact you to arrange your orientation. During
orientation, UTS' comprehensive benefits will be explained to you.


The following forms should be filled out and signed:

-      Ultratech Stepper, Inc., Employment Application (avoid "See Resume")

-      W-4 Tax Withholding Form

-      Employment Eligibility Verification (Form I-9). Fill out and sign Section
       1. Bring with you to the orientation the appropriate documents shown in
       Section 2 - either one document from List A OR one document from List B
       AND one document from List C.

-      Employment Agreement

-      Release Authorization

-      Emergency Contact Form

Providing Ultratech Stepper, Inc., with these forms and the appropriate
documents at orientation is a condition of employment with Ultratech Stepper,
Inc. We must receive the original documents and make copies for our files in
order to comply with the Immigration Reform and Control Act, which was signed
into law on November 6, 1986. This law requires employers to verify that all new
employees hired are authorized for employment in the U.S.

If you have any questions, please call Carmine Renzulli at (408) 577-3006. If
you agree with the terms of this offer and wish to become part of Ultratech
Stepper, Inc. and our exciting future, please indicate your acceptance by
signing below and returning the original to the Human Resources Department.

Ultratech Stepper, Inc. is an exciting and rewarding environment in which to
work. We look forward to welcoming you to our organization.



/s/ ARTHUR W. ZAFIROPOULO                    /s/ BRUCE R. WRIGHT
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Presented by:                                Accepted by:

Arthur W. Zafiropoulo                        Bruce R. Wright

President & CEO

Date: 4/20/99                                Date: 20 APR 99
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