| 摘要 |
PROBLEM TO BE SOLVED: To provide an inspection method of a mask pattern enabling an inspection to be performed even for a region where vignetting occurs. ! SOLUTION: A mask is mounted on a stage, and an optical image obtained by emitting light to an inspection region where a pattern of the mask is formed is compared with a reference image, and a place in which a difference between both images exceeds a predetermined threshold value is determined as a defect. The emission of the light to the mask is performed operating autofocusing means. When a pellicle is not mounted on the mask, a first threshold value is used, and when the pellicle is mounted on the mask, the first threshold value is used for a comparison between the optical image of a region where the region occurred with vignetting due to the pellicle is not overlapped with the inspection region and the reference image, and a second threshold value relatively looser in sensitivity than the first threshold value is used for the comparison between the o |
