EL SEGUNDO, Calif. June 2004 - International Rectifier Corporation (NYSE:IRF), a world leader in power management technology, today announced that it has entered into a definitive agreement to acquire the specialty silicon epitaxial services business of ATMI, Inc. (Nasdaq: ATMI), subject to customary closing conditions and certain third-party approvals.

International Rectifier (IR) has been a major, long-term customer of ATMI’s specialty epitaxial services business, located in Mesa, Arizona. IR CEO Alex Lidow said, "This group has provided excellent service to us over the years, and we are excited to have these employees join the IR team. They will bring innovative knowledge and expertise in specialty silicon and silicon germanium epitaxy, as well as key intellectual property for improving epitaxy deposition throughput and lowering production costs."

Under the terms of the agreement, IR will pay ATMI up to $41 million in cash for the operations and assets of the group, including related intellectual property, fixed assets, and inventory. Approximately 90 employees will join IR as part of the agreement. The transaction is expected to close in the September quarter, and IR expects the acquisition to be accretive within the first 12 months.

About International Rectifier

International Rectifier (NYSE:IRF) is a world leader in power management technology. IR's analog and mixed signal ICs, advanced circuit devices, integrated power systems and components enable high performance computing and reduce energy waste in motors, the world's single largest consumer of electricity. Leading manufacturers of computers, energy efficient appliances, lighting, automobiles, satellites, aircraft, and defense systems rely on IR's power management benchmarks to power their next generation products. For more information, go to www.irf.com.

The foregoing material includes some "forward-looking statements" as that term is defined in the Private Securities Litigation Reform Act of 1995. The materials presented can be identified by the use of forward-looking terminology such as "anticipate", "believe", "estimate", "may", "should", "will", or "expects" or the negative or variations thereof, whether set out in the text of documents or in graphs. Such forward-looking statements are subject to a number of uncertainties and risks, and actual results may differ materially from those projected. Factors that could affect the company’s actual results include greater than expected costs of implementing company restructuring plans; changes in assumptions or events that adversely affect the timing and realization of anticipated cost savings from restructuring plans and the amount of anticipated charges; the failure of market demand to materialize as anticipated; the effectiveness of cost controls and cost reductions; pricing pressures; unexpected costs associated with cost-reduction efforts, including reductions in force and the transfer, discontinuance, divestiture or consolidation of product lines and equipment (including, without limitation, those associated with the company’s restructuring initiatives); product claims, litigation, investigations, returns and recalls, and the cost of defense; introduction, acceptance, availability, and continued demand and growth of new and high-performance products; delays in transferring and ramping production lines or completing customer qualifications (including, without limitation, those associated with the company’s restructuring initiatives); company and market impact due to the cancellation or delays in customer and/or industry programs and/or orders; unfavorable changes in industry and competitive conditions; economic conditions in the company’s markets around the world and the timing of changes in market conditions; the company’s mix of product shipments; the success of working capital management programs; failure of suppliers and subcontractors to meet their delivery commitments; changes in interest and investment rates; impacts on our business or financial condition due to changes in currency valuation; impact of changes in accounting methods; the impact of changes in laws and regulations, including tax, trade and export regulations and policies; the initiation of or actual results of any outstanding patent and other litigation, whether asserted by or against us; impacts on our royalties from patent licensee redesign, a decline in sales by licensees, or change in product mix to non-infringing devices; and other uncertainties disclosed in the company’s reports filed with the Securities and Exchange Commission, including its most recent reports on Form 10-K and 10-Q. Additionally, to the foregoing factors should be added the financial and other ramifications of terrorist actions.

Company Contact

Investor Relations: Steve Harrison, 310.252.7731

Media Relations: Graham Robertson, 310.726.8512

Website: www.irf.com.