METHOD FOR DETECTING END POINT OF TREATMENT IN SUBSTRATE TREATMENT DEVICE

摘要

PROBLEM TO BE SOLVED: To detect the end point of the treatment of an article being treated accurately by monitoring the variation of a film thickness on the surface of the article in real time according to a simple treatment procedure. SOLUTION: An article 3 being treated comprising a substrate 5 having a metal thin film 4 deposited on the surface is subjected to treatment for removing the metal thin film 4 by polishing in a treatment liquid tank 1. In order to measure the film thickness of the metal thin film 4, a light projecting means 10 including a light source 12 and a light projecting lens 13, and a means 11 for receiving reflected light from the article 3 are provided. A light receiving signal of the light receiving means 11 is converted by an A/D converter 21 into a digital signal which is then passed through a filter 22 for the purpose of averaging, noise removal and smoothing. A light receiving signal from the reticle 3 is differentiated by a differentiation circuit 23 to produce data concerning to the film thickness variation rate of the metal thin film 4 during the treatment. COPYRIGHT: (C)2003,JPO