SUBSTRATE INSPECTION METHOD AND SUBSTRATE INSPECTION APPARATUS

PROBLEM TO BE SOLVED: To adjust the intensity of illumination light without having to separately provide a special mechanism for adjusting laser intensity and to inspect foreign matters with light intensity adjusted in the case of adjusting the intensity of illumination light according to an object to be inspected. SOLUTION: When an irradiation region of the inspection light is shifted from a low-reflection section to a high-reflection section for irradiation, inspection light undergoes off-control to reduce its light intensity immediately prior to the shift. When the irradiation region of the inspection light is reversely shifted from the high-reflection section to the low-reflection section for irradiation, the inspection light undergoes on-control to increase light intensity and make it return to light intensity of regular time immediately prior to the shift. Since a laser beam to be the inspection light is gradually reduced in light intensity during a shift from an on-state to an off-state and gradually reversely increased in light intensity during a shift from an off-state to an on-state, by using these characteristics of the laser beam, it is possible to adjust the intensity of illumination light without having to separately provide a special mechanism for adjusting laser intensity and inspect foreign matters with the light intensity adjusted by performing on/off control. COPYRIGHT: (C)2011,JPO&INPIT