Reflected light intensity ratio measuring device, device for measuring light energy absorption ratio and heat treatment apparatus

摘要

A measuring optical system for emitting and receiving light is fixedly installed in a ceiling portion of a measuring device, and a wafer holding part for supporting a semiconductor wafer is provided in a bottom portion of the measuring device. A support table is horizontally laid between support pins of the wafer holding part, and a calibration standard member for calibration is placed on an upper surface of the support table. When a semiconductor wafer is supported by the support pins, light emerging from the measuring optical system impinges upon the semiconductor wafer, and the reflection intensity of the light is measured. When no semiconductor wafer is supported by the support pins, light emerging from the measuring optical system impinges upon the calibration standard member, whereby the calibration can be done at any time.