Patent ID: 8508727

Claim:
A defect inspecting apparatus, comprising: an illumination optic system configured to irradiate slit-like shaped laser beams upon a surface of an inspection target substrate; a detection optic system, having a first detector and a second detector configured to detect light initially radiated from said illumination optic system and thereafter scattering upon the surface of said inspection target substrate, the second detector being disposed in a direction different from that of said first detector, with respect to the surface of said inspection target substrate; and a processing portion configured to compare a first characteristic quantity upon basis of a first scattering light detected by said first detector of said detecting optic system, and a second characteristic quantity upon basis of a second scattering light detected by said second detector of said detection optic system, and thereby conducting a classification of defects; wherein said first scattering light is detected under an optical condition differing from said second scattering light, in at least one of: an illumination angle of said illumination optic system, a direction of illumination of said illumination optic system, a detection angle of said detection optic system, an intersection angle of said detection optic system, a magnification of said detection optic system, or an optical filter of said detection optic system.