Patent ID: 8548223

Claim:
An inspection system comprising: an optical image data unit for acquiring optical image data of a mask having predetermined patterns formed thereupon; a reference image data unit for creating reference image data associated with the optical image data from design pattern data used as a basis to form the patterns; a regional image data unit for creating regional image data that includes pixel values denoted by multi-valued resolution based upon importance level information relating to the patterns, from region data including at least one portion of the patterns defined in the design pattern data; a comparator for defect determination on a pixel-by-pixel basis, comparing the optical image data within a region denoted by the regional image data, with the reference image data, by using one of either a plurality of threshold values determined by each pixel value within the regional image data, or a plurality of defect determination methods; a MEEF (Mask Error Enhancement Factor) regional image data creating unit for creating image data of a section whose MEEF is equal to or greater than a predetermined value, from the region data including at least one portion of the patterns defined in the design pattern data; and an interface unit that outputs, to a lithography simulator, optical image data of a section determined from the results of the comparison to have MEEF equal to or greater than the predetermined value, and irrespective of whether the results of the comparison by the comparator indicate a defect determination in the section.