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Advanced Energy Announces Definitive Agreement to Acquire Aera Japan Ltd.

Leading mass flow controller provider will expand product line and market reach

Fort Collins, Colorado (November 19, 2001)—Advanced Energy Industries, Inc. (Nasdaq: AEIS) and Aera Japan Ltd. today announced a definitive agreement under which Advanced Energy will acquire Aera. Aera is a privately-held company headquartered in Hachioji, Japan and is a leading supplier of mass flow controllers to the semiconductor capital equipment industry. The acquisition is expected to be completed as a cash transaction valued at approximately $48 million, in addition to the assumption of bank debt.

Doug Schatz, chairman and chief executive officer of Advanced Energy said, “Aera is a leader in the mass flow control market with a large installed base of mass flow control products and gas delivery subsystems at key OEMs and end users within the semiconductor industry. Aera’s established customer base and infrastructure will advance our strategy to add critical subsystems around the semiconductor process chamber by providing a leading and diverse product line.

“Power delivery and mass flow control are two of the largest segments of the components and subsystems market for semiconductor equipment. The combination of power delivery and gas delivery subsystems will allow AE to provide the two most important systems that affect the wafer, increasing the value we bring to our customers,” said Mr. Schatz.

Aera’s products expands Advanced Energy’s offering of critical solutions that enable the plasma-based manufacturing process used in the manufacture of semiconductors. Advanced Energy’s current product offering includes components for power delivery and control, remote plasma clean, temperature sensing, temperature management, process instrumentation, and an emerging technology in mass flow control acquired through the purchase of EMCO in January 2001.

“Our acquisition of EMCO enabled us to enter the mass flow control market with a highly disruptive technology that earned its first major semiconductor industry design win last quarter. The EMCO Mach OneÔ technology is complementary to Aera’s product line and will leverage Aera’s infrastructure as it targets volume production and an expanded customer base. The combination of the EMCO and Aera technologies will provide Advanced Energy with the most complete product line in the mass flow control market, and enhance both companies’ expertise in this sector,” continued Mr. Schatz.

Peter Aoyama, president of Aera Japan Ltd. said, “Advanced Energy’s infrastructure and global customer base will extend the reach of Aera’s diverse mass flow product line. We will combine our expertise in mass flow technology with Advanced Energy’s innovative Mach OneÔ technology platform to bring high-value gas delivery management solutions to our customers.”

Aera was founded in 1976 as Nippon Tylan, and later renamed Aera in 1996. The company provides the semiconductor industry with a broad range of efficient, reliable and accurate process control equipment and support. Aera’s product lines include digital mass flow controllers, pressure-based mass flow controllers, liquid mass flow controllers, ultrasonic liquid flow meters and liquid vapor delivery systems. For the fiscal year ended June 2001, revenues were $114 million and operating income was $17 million. The company employs 205 people with offices in 6 locations worldwide, including Aera Corporation, its US headquarters in Austin, Texas.

About Advanced Energy
Advanced Energy is a global leader in the development, marketing, and support of technology solutions that are critical in the manufacture of semiconductors, data storage products, and flat panel displays as well as in applications that involve surface modification and process power control. Original equipment manufacturers (OEMs) and end-users around the world depend on AE products when plasma-based technology plays a central role in their manufacturing process. AE offers a comprehensive line of technology solutions including power conversion and control systems, process monitoring and control tools, ion-beam sources, dynamic temperature control products, and plasma abatement systems. AE technology solutions are sold and supported globally by direct offices, representatives, and distributors. Founded in 1981, AE is a publicly held company traded on Nasdaq National Market under the symbol AEIS.

Conference Call
Management will host a conference call today, Monday, November 19th at 9:00 am Eastern time to discuss this announcement. You may access this conference call by dialing 877-282-0743. International callers, please dial 703-871-3073. For a replay of this teleconference, please call 703-925-2533, passcode 5672900. The replay will be available through Monday, November 26, 2001. There will also be a webcast available at www.advanced-energy.com .

Safe Harbor Statement
This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These forward-looking statements represent the companies' reasonable judgments with respect to future events, but are subject to risks and uncertainties that could cause actual results to differ materially from those described in the forward-looking statements. Among the factors that could cause such different results are: the conditions to the merger might not be met; the merger might not be completed for other reasons; we might not be able to integrate the companies' operations successfully; integration of the companies' operations could result in unanticipated costs or substantial diversion of management's attention; and the projections on which the companies relied to determine the advisability of the merger ultimately might not prove to have been accurate. These and other cautionary statements are set forth in Advanced Energy's SEC reports, including annual reports on Form 10-K and quarterly reports on Form 10-Q. Neither Advanced Energy Industries, Inc. nor Aera Japan Ltd. assumes any obligation to update the information in this press release. 

For more information:
     Advanced Energy Corporate Website:  www.advanced-energy.com
    Aera Japan Ltd. Corporate Website:  www.massflow.com