PATTERN DEFECT INSPECTION DEVICE AND PATTERN DEFECT INSPECTION METHOD

摘要

PROBLEM TO BE SOLVED: To adjust automatically a threshold of defect determination corresponding to characteristic fluctuation of a pattern image detection part 110 or individual dispersion of a surface characteristic of a wafer 6 to be inspected. SOLUTION: An image processing part 120 has a constitution including a defect signal extraction part 21 for extracting a defect signal based on a differential image between a detection image of some domain on the surface of the wafer 6 to be inspected and a detection image of another domain having the same pattern as the domain; a defect signal accumulation part 23 for accumulating a defect signal amount of each pixel, and calculating its frequency distribution and dispersion relative to all pixels in the differential image; an offset calculation part 24 for calculating an offset amount of the frequency distribution by comparing the calculated dispersion with a dispersion of a reference frequency distribution acquired from a reference wafer 6 to be inspected; and a defect determination part 25 for correcting a reference defect determination threshold set beforehand by the offset amount, and performing defect determination of the defect signal relative to a defect image based on the corrected defect determination threshold. COPYRIGHT: (C)2009,JPO&INPIT