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

June 28, 1999—The RFMS RF Metrology System, which solves many problems process engineers encounter with CVD and etch tools, is now available from Advanced Energy Industries, Inc. (Nasdaq: AEIS). The RFMS system allows tools to accommodate new processes and smaller geometries. It increases product yields and lowers costs by solving—and implementing controls for—these historically difficult problems:

• End-point detection
• Within wafer excursion detection
• Wafer-to-wafer excursion detection

Copies of the brochure describing this RF Metrology System are available at no charge by sending a request via e-mail to sales.support@aei.com or from the web at advanced-energy.com.

Advanced Energy Industries, Inc. is a leading developer and manufacturer of power supplies and related products that are critical in the manufacturing of semiconductors, data storage devices, flat panel displays, and other industrial products using thin-film technology such as glass coatings, decorative coatings, and optical coatings. Founded in 1981, AE is a publicly held company traded on Nasdaq, symbol AEIS. Its web site address is advanced-energy.com.