Patent attributes
The present invention relates to detection of defects with simple specification of the coordinates, in the inspection of an object having a plurality of patterns in which a portion having the two-dimensional repetition and portions having the repetition only in the X direction and in the Y direction are mixedly present. The cross comparison between a notice point and comparison points, for example which are repetitive pitches away from the notice point, is carried out, and only the portion having the difference which can be found out with any of the comparison points is extracted as a defect candidate, which results in that the portion having the two-dimensional repetition as well as the portion having the repetition only in the X direction or in the Y direction can be inspected. As a result, while the portion, such as an isolated point, having no repetition both in the X direction and in the Y direction is extracted as the defect candidate, the defect candidate is not treated as the defect in the case where the defect candidate of interest occurs regularly in a plurality of objects to be inspected, so that such a defect candidate is excluded to extract only a true defect.