WAFER DETECTION SYSTEM IN CASSETTE, WAFER CONVEYING APPARATUS AND WAFER PROCESSING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a wafer detecting system in a cassette which can efficiently detect a wafer and can take out the wafer from the cassette even when the wafer is contained obliquely in the cassette. SOLUTION: The wafer detecting system in the cassette includes a detector 6 having a light emitting element 6a and a photodetecting element 6b disposed before and after the open cassette 12 for detecting the wafer 14 in response to the photodetecting signal of the photodetecting element 6b, a moving mechanism 5 for relatively vertically moving the detector 6 to the open cassette 12, a shelf position signal generator for generating a signal corresponding to either each shelf of the open cassette 12 or a space between the shelves by vertically moving in cooperation with the moving mechanism 5, and a detecting circuit 8 for detecting the wafers 14 set to shelves different in steps based on the detection signal from the detector 6 and the signal from the shelf position signal generator. COPYRIGHT: (C)2005,JPO&NCIPI