Patent ID: 7453561

Claim:
An apparatus for inspecting a foreign particle defect, comprising: an illuminator which irradiates a surface of a sample with an illuminating beam; a detector which collects through an objective lens scattered reflected light from the surface of the sample as illuminated by the illuminator and detects the collected light with a detecting device; and a signal processor which processes a signal obtained as a result of the detection of the scattered reflected light by the detecting device of the detector so as to detect a foreign particle defect on the surface of the sample, wherein the detector includes a converging optical system which collects the scattered reflected light from the surface of the sample, and an aberration corrector which corrects an aberration of the converging optical system, wherein the illuminating beam emitted from the illuminator toward the surface of the sample is formed in a shape long in a direction, and emitted from a direction oblique to the surface of the sample, and wherein the converging optical system of the detector includes a reflection optical system and a refraction optical system, and the aberration corrector corrects the aberration of the converging optical system by changing a reflection condition of the reflection optical system or a refraction condition of the refraction optical system.