ETCHING METHOD AND APPARATUS

摘要

The present invention consists in an etching method and apparatus wherein an optical image which is reflected from a region of a dicing stripe pattern on a substrate to-be-etched, such as a semiconductor wafer, is focused by a projecting optical system during selective etching. The focused pattern is converted into an image signal by an image detector, and a change of contrast in the region of the dicing stripe pattern is determined from the image signal. Based on this, an ending time for the etching can be decided from the change of contrast.