Patent ID: 6342166
Filing Date: 2002-01-29
Classification: B24B,H01L

Abstract:
A method of detecting an end point of polishing of a wafer comprising the steps of:providing a color identifying sensor to recognize a color component of light; inputting data on a color component of a substance of the wafer to the color identifying sensor, in which said color identifying sensor displays an ON-state when the color component is detected and an OFF-state when the color component is not detected; rotating the wafer to start to polish the wafer; emitting light from a light source to the wafer; irradiating a point, except for the central point, on the surface of the wafer with the light; converging the light reflected by the point of the wafer to an optical fiber; counting the number (m) of times of OFF-states for each of predetermined periods of time by the color identifying sensor; and finishing polishing of the wafer when the number of times (m) coincides with the number (n) of times of off-states indicating an optimum end point of polishing of the wafer in the predetermined period of time.