Patent ID: 6831737
Filing Date: 2004-12-14
Classification: G01N

Abstract:
A pattern defect inspecting apparatus, comprising:a stage capable of placing a substrate to be inspected thereon and moving in X and Y directions; an ultraviolet laser light source for emitting ultraviolet laser light therefrom; an illumination optical system including a multispot shaper for forming a plurality of light-emitting images from the ultraviolet laser light emitted from said ultraviolet laser light source, a coherence reduction optical system for reducing coherence with respect to the ultraviolet laser light comprised of the plurality of light-emitting images formed by said multispot shaper, and a converging optical system for allowing a plurality of pieces of the ultraviolet laser light reduced in coherence through said coherence reduction optical system to converge on a pupil position of an objective lens, said illumination optical system applying the plurality of pieces of ultraviolet laser light focused on the pupil of the objective lens by said converging optical system onto the substrate to be inspected; a detection optical system including an image forming optical system for focusing an ultraviolet reflected light image from a circuit pattern formed on the substrate to be inspected, and an image sensor for receiving the ultraviolet reflected light image focused by the image forming optical system and converting the same into an image signal; an image signal processing circuit including an A/D converter for A/D converting the image signal obtained from the image sensor of said detection optical system, and a comparator for comparing a detected digital image signal converted by the A/D converter with a reference digital image signal to thereby detect a defect or a defect candidate in the circuit pattern and outputting inspection information; and an amount-of-light monitor unit for allowing some of the ultraviolet laser light emitted from the ultraviolet laser light source to branch and detecting the intensity thereof.