| 摘要 |
During the polishing of a wafer 2, the wafer 2 is illuminated with measuring light emitted from a light source 21, and the spectroscopic intensity of the reflected light is detected by a linear sensor 31. The signal processing part 11 monitors the polishing state of the wafer 2 on the basis of detection signals from the sensor 31, and detects the polishing endpoint of the wafer 2. The shutter mechanism control part 14 controls the motor 13b of the shutter mechanism 13 in response to the polishing endpoint detection signal from the signal processing part 11, and causes a light blocking member 13a to advance into the light path of the measuring light, so that the measuring light is blocked with respect to the wafer 2. As a result, the effect of the measuring light used for the monitoring of the polishing state on the object of polishing can be reduced. <IMAGE> |
