Patent ID: 8090186

Claim:
A pattern inspection apparatus comprising: an imaging unit which scans a substrate having a pattern formed thereon with a charged particle beam and detects charged particles generated from the substrate to acquire an image of the pattern; a matching unit which performs matching of CAD data for the pattern and the image; an arithmetic unit which extracts coordinates of a plurality of points on a line segment which is drawn by use of the CAD data and constitutes an arbitrary polygon figure, defines the extracted coordinates as a first coordinate group, specifies coordinates of edge points in the image that correspond to the plurality of points, defines the specified coordinates as a second coordinate group, calculates differences between the coordinates corresponding to each other from the first and second coordinate group, and calculates statistics each representing a degree of deviation in the matching based on the differences; a judgment unit which judges whether correction processing is required based on the statistics; a correction unit which performs the correction processing to correct the polygon figure when the judgment unit determines that the correction processing is required; and an inspection unit which inspects the pattern by comparing the corrected polygon figure with the image.