DEFECT INSPECTION METHOD AND APPARATUS THEREFOR

摘要

In order to effectively utilize the polarization property of an inspection subject for obtaining higher inspection sensitivity, for the polarization of lighting, it is necessary to observe differences in the reflection, diffraction, and scattered light from the inspection subject because of polarization by applying light having the same elevation angle and wavelength in the same direction but different polarization. When this is performed according to conventional techniques, a plurality of measurements by changing polarizations are required to cause a prolonged inspection time period that is an important specification of inspection apparatuses. Then, a plurality of polarization states are modulated in micro areas in the lighting beam cross section, images under a plurality of polarized lighting conditions are collectively acquired by separately and simultaneously forming the scattered light from the individual micro areas in the individual pixels of a sensor, whereby inspection sensitivity and sorting and sizing accuracy are improved without reducing throughput.