Exhibit 32.1

CERTIFICATIONS OF CHIEF EXECUTIVE OFFICER AND CHIEF FINANCIAL OFFICER

PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

I, Arthur Zafiropoulo, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002, that, to my knowledge:



| |  |  | the Quarterly Report of Ultratech, Inc. on Form 10-Q for the period ended April 2, 2011 fully complies with the requirements of
Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and
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| |  |  | the information contained in such Quarterly Report fairly presents in all material respects the financial condition and results of operations of
Ultratech, Inc.
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| |  |     |  |                                |  |  |  |                      |  | 
| |  | --- |  | ------------------------------ |  |  |  | -------------------- |  | 
| |  | By: |  | /s/ ARTHUR ZAFIROPOULO         |  |  |  | Date: April 29, 2011 |  | 
| |  |     |  | Name: Arthur Zafiropoulo       |  |  |  |                      |  | 
| |  |     |  | Title: Chief Executive Officer |  |  |  |                      |  | 

I, Bruce Wright, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to
Section 906 of the Sarbanes-Oxley Act of 2002, that, to my knowledge:



| |  |  | the Quarterly Report of Ultratech, Inc. on Form 10-Q for the period ended April 2, 2011 fully complies with the requirements of
Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and
| | - |  | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| |  |  | the information contained in such Quarterly Report fairly presents in all material respects the financial condition and results of operations of
Ultratech, Inc.
| | - |  | ----------------------------------------------------------------------------------------------------------------------------------------------------------------



| |  |     |  |                                |  |  |  |                      |  | 
| |  | --- |  | ------------------------------ |  |  |  | -------------------- |  | 
| |  | By: |  | /s/ BRUCE WRIGHT               |  |  |  | Date: April 29, 2011 |  | 
| |  |     |  | Name: Bruce Wright             |  |  |  |                      |  | 
| |  |     |  | Title: Chief Financial Officer |  |  |  |                      |  | 



|* | A signed original of this written statement required by Section 906 has been provided to Ultratech, Inc. and will be retained by Ultratech, Inc. and furnished to
the Securities and Exchange Commission or its staff upon request.
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