MATTSON TECHNOLOGY TO PRESENT AT JPMORGAN 32ND ANNUAL TECHNOLOGY & TELECOM CONFERENCE

FREMONT, Calif.- May 3, 2004 - Mattson Technology, Inc. (NASDAQ: MTSN), a leading supplier of advanced process equipment used to manufacture semiconductors, today announced that David L. Dutton, president and chief executive officer, and Ludger H. Viefhues, chief financial officer, will be presenting at the JPMorgan 32nd Annual Technology & Telecom Conference on Tuesday, May 4, 2004 at 11:00 a.m. Pacific Time. This year’s conference will be held May 3-6, 2004 at the Westin Hotel in San Francisco, California.

The presentation will be webcast live via the Internet, accessible on Mattson’s corporate website at www.mattson.com or http://equityconferences.jpmorgan.com/. In addition to the live webcast, a replay will be available to the public on the Mattson website for one week following the live broadcast.

About Mattson Technology, Inc.

Mattson Technology, Inc. is a leading supplier of semiconductor wafer processing equipment used in the fabrication of integrated circuits. The company’s dry strip and RTP equipment utilize innovative technology to deliver advanced processing capabilities on high-productivity platforms for the fabrication of current- and next-generation devices. Since beginning operations in 1989, the company’s core vision has been to help bring technology leadership and productivity gains to semiconductor manufacturers worldwide. For more information, please contact Mattson Technology, Inc., 47131 Bayside Parkway, Fremont, Calif. 94538. Telephone: (800) MATTSON/(510) 657-5900. Fax: (510) 492-5911. Internet: www.mattson.com.