| 摘要 |
PURPOSE:To accurately convert even a signal changing in a minute amount into a binary signal and to permit inspection with high accuracy by a method wherein a slicing level is changed corresponding to the ground portion under measurement, in a defect inspection device with a reticle patern which is used in manufacture of semiconductor integrated circuits. CONSTITUTION:A circuit for effecting the slicing method is provided in a slicing section within a control unit. A slicing level at the middle between white and black, i.e., less than 50%, is set for the black part, a slicing level higher than 50% is set for the white part, and a slicing level at the center between white and black, i.e., at 50%, is set for the boundary part. By so doing, it becomes possible to accurately convert even a signal changing in a minute amount from the white or black level into a binary signal without the need of using complicate means. |
