MATTSON TECHNOLOGY ANNOUNCES THIRD QUARTER FINANCIAL RESULTS

Revenue Grows 21%, Returns to Profitability

FREMONT, Calif. — October 21, 1999 — Mattson Technology, Inc. (Nasdaq:MTSN), a leading supplier of advanced process technology for semiconductor manufacturing, today announced financial results for the third quarter of 1999. Net sales for the third quarter of 1999 were a record high at $29.2 million,compared to $9.4 million for the third quarter of 1998, an increase of 211 percent. The Company recorded net income for the third quarter of $0.3 million or $0.02 per diluted share, compared to a net loss of $14.8 million or $1.00 per diluted share for the third quarter of 1998. Third quarter bookings were also at a record level of $35.6 million, up from $11.0 million for the third quarter of 1998, an increase of 224 percent. Backlog increased 89 percent to $41.4 million, compared to $21.9 million at the end of the third quarter of 1998.

Quarter to quarter sales increased 21 percent, up from $24.1 million in the second quarter of 1999. Net income of $0.3 million, or $0.02 per diluted share for the third quarter of 1999 represents an increase from a net loss of $0.2 million, or 1 cent per diluted share, last quarter. Bookings increased 20 percent, up from $29.6 million in the second quarter of 1999, resulting in a book to bill ratio of 1.2 to 1.0.

Brad Mattson, CEO of Mattson Technology, stated, "I'm extremely pleased that we reached record highs in revenue and bookings even though many analysts believe this recovery is just starting. We have made good progress at ramping our production capacity, getting new products into the field, and staffing up key positions. I think we are well positioned to grow as the industry continues to recover."

About Mattson Technology

Mattson Technology Inc., is a leading supplier of thermal, plasma and wet semiconductor processing equipment. The company's products combine advanced process technology on a high productivity platform, 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, Asia/Pacific and Japan. For more information, please contact Mattson Technology Inc., 2800 Bayview Drive, Fremont, Calif. 94538. Telephone: (800) MATTSON. Fax: (510) 657-0165. Internet:www.mattson.com