For more information, contact:

Richard Beck Advanced Energy Industries 970/407-6204

Catherine Roberts Financial Relations Board/San Francisco 415/986-1591

FORT COLLINS, Colorado (May 6, 1998)—Advanced Energy Industries, Inc. (Nasdaq:AEIS) has signed a three-year contract with a leading semiconductor equipment company to provide a complete range of DC, Radio Frequency (RF) and mid-frequency power conversion systems and matching networks for use in PVD, HDPCVD, CVD and etch. Should this customer purchase all of the defined products in the quantities estimated in the contract, the potential value of the contract would exceed $180 million. This is a renewal of a previous three-year contract.

Douglas S. Schatz, Chief Executive Office of Advanced Energy, said, “Our partnership with this company began in 1985 and continues to grow stronger. Over this time, we have developed new systems that enhance the efficiency and effectiveness of their production processes and have provided them with global support of our systems. Today, we are the major supplier of power conversion and control systems for their plasma processing needs.”

Schatz said he believes the current contract has the largest potential value of any contract in the industry. The power conversion control systems to be provided under this contract will be used on new 300 mm tools as well as some advanced technology 200 mm tools.

Safe Harbor Statement
Except for any historical information contained herein, the matters discussed in this news release are forward-looking statements that involve risks and uncertainties, including the realization of the potential value of this contract, the achievement of goals established by the Company to improve gross margin and maintain operating expenses in line with revenue, continued sales growth in non-semiconductor areas, and other risks detailed from time to time in the Company’s Securities and Exchange Commission reports, including the Company’s recent Prospectus, Form 10-K and Forms 10-Q. The Company continues to be susceptible to fluctuations in quarterly and annual revenues and operating results. The Company assumes no obligation to update the information in this release.

About the Company
Advanced Energy Industries, Inc. was founded in 1981 and is the leading manufacturer of power delivery systems that are critical in the manufacturing of semiconductors, data storage media, flat panel displays, and other products using thin-film technology. Within its comprehensive product portfolio of direct current (DC), low/mid-frequency and radio frequency (RF) solutions, the company sells hundreds of different products critical in the manufacture of compact disks, digital video disks, flat panel displays, the most popular logic semiconductor devices, among many other applications. The Company’s stock is traded on Nasdaq under the symbol AEIS.