Temperature measuring apparatus and temperature measuring method

Abstract

A temperature measuring apparatus includes a light source, a first splitter, a second splitter, a reference beam reflector, an optical path length adjuster, a reference beam transmitting member, a first to an nth measuring beam transmitting member and a photodetector. The temperature measuring apparatus further includes an attenuator that attenuates the reference beam reflected from the reference beam reflector to thereby make an intensity thereof closer to an intensity of the measurement beam reflected from the temperature measurement object.

What is claimed is: 
     
         1 . A temperature measuring apparatus comprising:
 a light source;   a single splitter for dividing a light beam emanated from the light source into a reference beam and a first to an nth measuring beam, n being larger than 1;   a reference beam reflector for reflecting the reference beam coming from the splitter;   an optical path length adjuster for adjusting an optical path length of the reference beam reflected from the reference beam reflector;   a reference beam transmitting member for transmitting the reference beam coming from the splitter to a reference beam irradiation position from which the reference beam is irradiated onto the reference beam reflector;   a first to an nth measuring beam transmitting member for transmitting the first to the nth measuring beam coming from the splitter to measuring beam irradiating positions from which the measurement beams are irradiated onto a first to an nth measurement points of a temperature measurement object; and   a photodetector for measuring an interference between the reference beam reflected from the reference beam reflector and the first to the nth measuring beam reflected from the temperature measurement object,   wherein the optical path lengths of the first to the nth measuring beam from the splitter to the temperature measurement object are different from each other.   
     
     
         2 . The temperature measuring apparatus of  claim 1 , wherein the apparatus is configured to measure temperature of a substrate to be processed by a substrate processing apparatus as the temperature measurement object, and the first to the nth measuring beam transmitting member are arranged in the substrate processing apparatus such that the first to the nth measuring beam are irradiated onto a plurality of measurement points in a surface of the substrate.