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Under the terms of the definitive agreement, Advanced Energy will purchase Fourth State Technology for cash, including an earn out provision, which will entitle Fourth State to receive an additional payout based on the profitability of the business unit over a three year period. Consummation of the transaction is subject to approval by Fourth State Technology shareholders and certain other conditions. The acquisition is expected to close on September 3, 1998.

Fourth State Technology is a process control company whose products are used to monitor the RF power process, collect data and provide an analysis of data for process control and improvements. The current Advanced Energy instrumentation product family will be integrated with the product family manufactured by Fourth State Technology.

Terry Turner, 40, President of Fourth State Technology, will become a vice president with Advanced Energy, in charge of the expanded instrumentation business unit, which will operate out of Austin, Texas.

Douglas S. Schatz, Advanced Energy’s Chairman and Chief Executive Officer, said, “Fourth State’s RF instrumentation products are recognized as some of the industry’s top RF power monitoring and data collection systems. The integration of Fourth State’s capabilities will provide additional revenue opportunities for Advanced Energy in the worldwide RF power market.”

A spin off of Sematech over six years ago, Fourth State Technology has a customer base of industry-leading companies in the semiconductor industry, with over 250 sites around the world. Deloitte and Touche LLP, financial advisors to Fourth State Technology, anticipate that the business combination will provide immediate leadership for the industry in advanced RF process control.

The acquisition of Fourth State Technology is Advanced Energy’s latest move in a global expansion into the RF market. In June, the Company announced the acquisition of RF Power Products of Voorhees, New Jersey, a manufacturer of RF power systems for OEMs in the semiconductor, flat panel display, thin film disc media and analytical instrument markets. The RF Power Products acquisition is scheduled for completion in October 1998.

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 approval of the acquisition by Fourth State Technology’s shareholders and certain other risks detailed from time-to-time in the Company’s Securities and Exchange Commission reports, including Form 10-K and Form 10-Q. The Company continues to be susceptible to fluctuations in quarterly and annual revenues and operating results and to the effects of economic conditions in Asia. Advanced Energy Industries assumes no obligation to update the information in this release.

Advanced Energy Profile
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 applications ranging from 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.

For more information, access Advanced Energy’s web site at www.advanced-energy.com or for information via fax, no cost, dial 800-PRO-INFO, code AEIS.