| 摘要 |
A piezoelectric gripping system for firmly securing a semiconductor wafer (102) or other workpiece onto a robot transfer mechanism blade (100) during transfer of the semiconductor wafer between wafer fabrication processing stations. The piezoelectric grippers (106 a-d) of the system are mounted on the blade, and move to engage the outer circumference of the semiconductor wafer upon application of an incremental voltage supplied via an electrical circuit (299) to the grippers. Once a gripper is in contact with the wafer, the voltage to that gripper is held constant to prevent further elongation of the gripper. Once all of the grippers are in contact with the wafer, the voltage to each gripper is increased by a predetermined voltage to thereby increase the force exerted by each gripper on the wafer to firmly secure the wafer to the blade. Thereafter, the blade may transfer the semiconductor wafer at extremely high speeds without the wafer moving with respect to the blade. <IMAGE> |
