Contact: Keithley Instruments, Inc.
28775 Aurora Road
Cleveland, Ohio 44139

Keithley Instruments Receives Order for Multiple S680 Parametric Test Systems from Leading Korean Fab

Cleveland, OH - September 1, 2004 - Keithley Instruments, Inc. (NYSE: KEI), a leader in solutions for emerging measurement needs, today announced it has received a multi-fab, multiple-system order from a leading Korean semiconductor manufacturer for its S680 DC/RF Parametric Test System. The multi-million dollar order represents tools for production process control of both 200mm and 300mm wafers. "One reason the customer chose the S680 was because it demonstrated higher throughput in a head-to-head benchmark against the competition," stated Mark Hoersten, Keithley's vice president for business development. "Furthermore, the unique architecture of the S680 provided the Integrated Circuit (IC) maker with superior measurement results at the probe tip for better process control of its flash memory devices."

Keithley's Model S680 DC/RF Parametric Test System, introduced in 2003, is designed for wafer-level parametric testing of advanced logic, memory, and analog ICs. In a single test system, it combines high DC sensitivity, femtoamp-level resolution, and RF s-parameter measurements up to 40GHz. This provides the industry's highest throughput and a lower cost of ownership for measurements at the 90nm node and beyond.

About Keithley Instruments, Inc. With more than 50 years of measurement expertise, Keithley Instruments has become a world leader in advanced electrical test instruments and systems from DC to RF (radio frequency) geared to the specialized needs of electronics manufacturers for high performance production testing, process monitoring, product development, and research. By building upon our strength in electrical measurement solutions for research, Keithley has become a production test technology leader for the semiconductor, wireless, optoelectronics, and other precision electronics segments of the worldwide electronics industry. The value we provide to our customers is a combination of precision measurement technology and a rich understanding of their applications to improve the quality, throughput, and yield of their products.

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