GSI Group Announces
Shipments of New Backside Die Marking System

WILMINGTON, MA, September, 2004 — GSI Group Inc. (Nasdaq: GSLI and TSX: GSI) announces multiple shipments of its new WaferMark® CSP200 backside die marking system, which uses laser technology to mark orientation and traceability information on each die on silicon wafers up to 200mm. The CSP200 is a second-generation die marking system that builds on GSI Group’ reputation as the leader in wafer and die marking systems. Initial shipments were to LCD driver chip manufactures in the Asia-Pacific region.

The fully automated, high throughput CSP200 provides the industry’s highest quality marks on a variety of wafer surface types. Highly accurate, the system is capable of marking die as small as 0.5mm in size, fulfilling the need for devices critical to the production of portable consumer electronic devices. Integrated mark inspection capability verifies the accuracy and quality of all marked die.

According to Gary Mezack, Director of Marketing for the company’s Laser Systems Group, “The use of chip scale packages and direct die attach in advanced and portable electronics is growing rapidly. Many of these devices must be marked as part of the manufacturing process and providing this capability at the wafer level yields significant advantages over marking after singulation. Reliable, cost-effective marking of these devices is critical for both traceability and product identification.”

Other system performance benefits critical to back end assembly operations include interfaces to prober map information, compatibility with back-ground and epoxy coated wafers, circuit overlay camera to prevent miss-marking, and factory host interfaces.