FREMONT, Calif.- April 30, 2002 - Mattson Technology (NASDAQ: MTSN), a leading supplier of advanced process equipment used to manufacture semiconductors, today announced that it plans to release first quarter financial results on May 14, 2002, before the open of the U.S. stock markets. The company will hold a conference call at 9:00 a.m. eastern time (6:00 a.m. pacific time) that day to discuss current results and business conditions.

A live webcast of the conference call and a replay of the call will be available to interested persons via Mattson's website, www.mattson.com under the "Investor Line" section.

About Mattson Technology, Inc.

Mattson Technology, Inc. is a leading supplier of semiconductor wafer processing equipment used in "front-end" fabrication of integrated circuits. The company is a market leader in dry strip and RTP equipment, and its products combine advanced process technology on high-productivity platforms backed by industry-leading support. Since beginning operations in 1989, the company’s core vision has been to help bring technology leadership and productivity gains to semiconductor manufacturers worldwide. Headquartered in Fremont, Calif., the company maintains sales and support centers throughout the United States, Europe and Asia. 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.