Patent ID: 7098055
Filing Date: 2006-08-29
Classification: B82Y,G01N,G01R,H01J,H01L

Abstract:
1. A defect inspection method comprising: a movement process of moving a moving stage mounted on a substrate as an object of inspection and having circuit patterns thereon to move the inspected substrate in a predetermined direction; an illumination process of radiating an illumination slit-shaped beam from an illumination optical system to the inspected substrate in a direction inclined at a predetermined gradient relative to the direction of a line normal to said inspected substrate with its longitudinal direction oriented almost perpendicularly to said movement direction of said moving stage; a defect process of receiving a scattered light reflected from said inspected substrate illuminated in said illumination process by using a detection optical system and converting said received light into detection image signals by using an image sensor provided in detection optical system; and a defect judging process of computing a variation of said detection image signals at corresponding locations including corresponding adjacent locations between areas where circuit patterns with substantially identical shapes are naturally repeated on the inspected substrate, and of extracting a signal indicating a defect such as a foreign particle whether said detection signal is exceeded by a criterion set on the basis of said computer variation.