| 摘要 |
PROBLEM TO BE SOLVED: To solve a problem in which trouble occurs in each processing stage when a plurality of wafers are mounted on each stage of a shelf in a pod and a problem in which a wafer can accurately be detected because of the increase of errors when the detection is carried out by moving a sensor by a driving means with an unstable speed, such as an air cylinder, when the sensor is moved by using such a driving means for simpler constitution of a device detecting the wafer. SOLUTION: The wafer processing apparatus is equipped with a transmission sensor 9 for wafer detection, a dock with an index means, and a transmission sensor for the dock. The wafer processing apparatus calculates the rate of the continuation of the signal from the wafer detecting transmission type sensor 9 and the continuation of the signal from the transmission type sensor for the dock corresponding to the index means and compares the ratio with a previously set value to judge the number of wafers 1. COPYRIGHT: (C)2004,JPO |
