Patent ID: 6559942
Filing Date: 2003-05-06
Classification: G01N,H01J,H01L

Abstract:
A method of etching a substrate in a process zone and monitoring the etching process, the method comprising:(a) etching a substrate by placing the substrate in the process zone, providing an energized process gas in the process zone, and exhausting the process gas, whereby the energized gas may generate a radiation emission; (b) determining completion of a first stage of the etching process by (i) detecting the intensities of one or more wavelengths of the radiation emission, (ii) generating a first signal in relation to the detected intensities, and (iii) evaluating the first signal; and (c) determining completion of a second stage of the etching process by (i) detecting the intensities of one or more wavelengths of a polarized radiation reflected from the substrate being etched, (ii) generating a second signal in relation to the detected intensities, and (iii) evaluating the second signal.