MICRO:Product Technology News (April '99)

The KA250 wafer carrier is molded of PEEK and a polycarbonate to ensure low-particulate operation and dimensional stability. The carrier's wafer and equipment contacts are made of Stat-Pro 3000, a static-dissipative PEEK material, while a polycarbonate is used in the frame and end wall. The design also ensures reliable equipment interface and robotic wafer transfer. StableWafer pocket design technology controls the wafer plane even when the wafer is removed from its pocket up to 21/2 in. from the fully seated position. This feature eliminates wafer chatter and flutter. Carriers can be colored red, blue, or green to differentiate wafer lots. End walls may also be a different color from the carrier's frame in order to extend color coding options. Additional identifying markers such as RF tags or adhesive bar code labels are also available. Designed for sub-0.15-µm metrology, the VeraSEM accommodates both 200- and 300-mm wafers and can be upgraded to measure critical dimensions on sub-0.13-µm geometries. The system's process variation monitoring technology uses a column design and special algorithms to measure line edge roughness, line edge width variation, and open or closed contact holes. A high-speed stage, fast wafer handling, and accurate measurement algorithms ensure high throughput. The Gencobot 9 servo-controlled robot offers repeatable indexing and transfer of wafers and flat-panel displays in vacuum processes >=10—8 torr. The robot's global positioning system ensures accurate transfer of 300-mm wafers. An optional yaw-axis feature eliminates the need for radial placement of process stations or cassettes around the robot. A variety of arm options permits the robot to transport an array of wafers, FPDs, and photomasks up