| 摘要 |
PURPOSE:To inspact a photo-mask accurately by obtaining measuring patterns, the directions of measurement therefor are varied at a unit of 45 deg., from the picture data of the photo-mask and detecting the changes of each pattern. CONSTITUTION:A photo-mask is read by a scanner and the picture data are obtained, and the data are binary-coded and memorized. The direction of reading is turned at the unit of 45 deg. in the memorized picture data, and four measuring patterns are acquired. The number of times where each measuring pattern is changed into values corresponding to the conductor section and non-conductor section of the photo-mask is detected, and the parity of the number of times is discriminated and ''0'' is outputted on an odd number and ''1'' on an even number. Each output is 1 because the measuring pattern values change twice in all of the directions of reading (a)-(d). The defects of the photo-mask such as a pin hole are detected by combining outputs corresponding to each measuring pattern. |
