MTSN Mattson Technology, Inc.

Mattson Technology, Inc. (NASDAQ: MTSN), a leading supplier of advanced process equipment used to manufacture semiconductors, announced that the company will host a conference call on Wednesday, April 27, 2011 at 5:30 p.m. Eastern Time (2:30 p.m. Pacific Time). The conference call will cover 2011 first quarter financial results and current business conditions.

Mattson will also web cast a slide presentation in conjunction with the conference call. To access the live web cast and slide presentation, please visit Mattson's website www.mattson.com under the 'Investors' section.

To access the live conference call, dial (970) 315-0417.

A digital replay of the conference call will be available on Mattson's website for one week following the live broadcast.

About Mattson Technology, Inc. Mattson Technology, Inc. is the leading supplier of dry strip equipment and the second largest supplier of rapid thermal processing equipment in the global semiconductor industry. The company's strip and RTP equipment utilize innovative technology to deliver advanced processing performance and productivity gains to semiconductor manufacturers worldwide for the fabrication of current- and next-generation devices. 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.

Mattson Technology Contact Andy Moring tel +1-(510) 492-6241 fax +1-(510) 492-5963 Andy.Moring@mattson.com Investor & Media Contact Laura Guerrant-Oiye Guerrant Associates tel 808-882-1467 lguerrant@guerrantir.com