METHOD FOR MEASURING PATTERN WIDTH DEVIATION, AND PATTERN INSPECTION APPARATUS

摘要

A pattern width deviation measurement method includes measuring width dimensions of a plurality of figure patterns in an optical image from data of gray-scale value profiles of the optical image, using a threshold of a gray-scale value level variably set depending on design dimension information including design width dimension of a corresponding figure pattern of a plurality of figure patterns, and at which influence of a focus position on width dimension becomes smaller, measuring width dimensions of a plurality of corresponding figure patterns in a reference image from data of gray-scale value profiles of the reference image, respectively using the threshold for the corresponding figure pattern of a plurality of figure patterns, and calculating, for each of measured width dimensions of a plurality of figure patterns in the optical image, an amount deviated from a measured width dimension of a corresponding figure pattern in the reference image.

主权项

1. A pattern width deviation measurement method comprising:
acquiring an optical image of a plurality of figure patterns formed on a mask substrate; generating a reference image of a region corresponding to the optical image, based on design data serving as a base for forming the plurality of figure patterns on the mask substrate; measuring width dimensions of the plurality of figure patterns in the optical image from data of gray-scale value profiles of the optical image, using a detection threshold of a gray-scale value level which is variably set depending on design dimension information including design width dimension of a corresponding figure pattern of the plurality of figure patterns, and at which influence of a focus position on width dimension becomes smaller; measuring width dimensions of a plurality of corresponding figure patterns in the reference image from data of gray-scale value profiles of the reference image, respectively using the detection threshold for the corresponding figure pattern of the plurality of figure patterns; and calculating, for each of measured width dimensions of the plurality of figure patterns in the optical image, a dimension deviation amount deviated from a measured width dimension of a corresponding figure pattern in the reference image, and outputting the dimension deviation amount calculated.