Robotic semiconductor wafer transporter with vertical photodetector array - scans detectors to determine which slots are occupied by wafers illuminated from emitter on robot arm

摘要

A light-emitting device (28) on the robot arm (16) is coupled to the array (300) of individually addressable photodetectors for checking the positions of wafers (201) in respective slots of a cassette. The robot has two wafer grippers (27) for cylindrical movement. The light emitters illuminate the photodetectors through a wafer boat (200) which is moved from a loading position to one within range of the robot. USE/ADVANTAGE - In integrated circuit mfr., setting time of processing machine is optimised so that another wafer can be supplied to it as soon as previous one has been removed.