For more information, contact:

Jim Donaldson Advanced Energy Industries, Inc. 970.407.6374

Marna Shillman Advanced Energy Industries, Inc. 970.407.6280 marna.shillman@aei.com

Fort Collins, Colo., October 16, 2002—Advanced Energy Industries’ (Nasdaq: AEIS) today announced that its Aera mass flow controllers (MFCs) were recently named the Default Standard for Mattson Technology, Inc.’s (Nasdaq: MTSN) Aspen strip platforms. The designation was awarded to Aera series FC-7700 and FC-7800 thermal MFCs, which have demonstrated excellent field performance in gas control applications. Mattson’s Aspen II and III systems provide photoresist and post-etch residue removal for 100-300 mm applications.

Michael Santiago, plasma division product marketing manager, commented, “Mattson Technology seeks to consistently provide our customers with improved products and services. We ultimately look for products and partners that we believe can help us achieve that, such as the Aera mass flow controllers from Advanced Energy. Advanced Energy provides Mattson with high value gas controllers as well as an integral network of customer support facilities.”

Doug Schatz, chairman and chief executive officer of Advanced Energy, noted, “We are very pleased to be named MFC Default Standard on Mattson’s strip platforms. We’ve partnered with Mattson for years, supplying Aera MFCs as well as power management products. With Advanced Energy’s investment earlier this year in three new Class 1000 cleanrooms in Taiwan, China, and Singapore, we can offer Mattson and its customers immediate, unsurpassed global MFC service and support.”

About Mattson Technology
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, RTP, wet processing and PECVD 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., 2800 Bayview Drive, Fremont, Calif. 94538. Telephone: (800) MATTSON/(510) 657-5900. Fax: (510) 226-8241. Internet:www.mattson.com

About Advanced Energy
Advanced Energy is a global leader in the development, marketing and support of components and sub-systems critical to plasma-based manufacturing processes used in the production of semiconductors, flat panel displays, data storage products, compact discs, digital video discs, architectural glass, and other applications that require precise thin-film processes. AE offers a comprehensive line of technology solutions in power, flow and thermal management, plasma and ion beam sources, and integrated process monitoring and control to original equipment manufacturers (OEMs) and end-users around the world. AE operates in regional centers in North America, Asia and Europe, and offers global sales and support through direct offices, representatives and distributors. Founded in 1981, AE is a publicly-held company traded on Nasdaq National Market under the symbol AEIS. For more information, please visit our corporate website: www.advanced-energy.com