| 摘要 |
PURPOSE:To make it possible to perform automatical reading without manual operation by a method wherein a resonator and a loop coil are embedded in a wafer transfer cassette corresponding to the wafer to be descriminated, and they provided with a sending section that sends sweep electromagnetic wave and a detecting section that reads the descriminating information for a wafer from the reflection wave produced by three resonance of the resonator. CONSTITUTION:A resonator circuit unit 4 consists of a loop coil 7 and one or plural seramic resonators 61-6n. The ceramic resonators 61-6n are have specific resonance frequency f1-fn, and the discriminating information for wafers is coded with the combination of the frequencies f1-fn. A control section 20 has input registers 24, 5 and 26. As for the contents of the input registers, the information contained in the obtained signals is taken out with a collation test section 27 and a constant mark test section 28 and is sent to the centralized computer that manages each production device. Information pulses are taken while the reflection wave from the ceramic resonators pass through a filter 14, detector 15, and an amplifying shaping device 23. And these effective information is obtained by feeding the pulses through the register 24, 25, and 26 and testing section 27 and 28. |
