| 摘要 |
PURPOSE:To enable a positioning in pattern inspection automatically and at a high accuracy by shifting a position of a movable detecting section in response to a calculation output on the basis of a signal from the fixed and movable detecting section. CONSTITUTION:A fixed detecting section 16 is set roughly over a predetermined unit pattern P3 for a photo mask 10 mounted on X-Y table 11 and the unit pattern P3 is compared with a reference pattern signal 22. Subsequently, the table 16 is shifted so that the pattern P3 is set at a predetermined position for the detection part 16. Subsequently, after a movable detecting section 17 is set roughly over a unit patter P4 to be compared, a pattern signal for the detecting sections 17, 16 is compared with the other. In this case, if there exists a displacement between the pattern signals, an operation decision circuit 21 is operated to actuate a motor 18 through a control circuit 24 and perform a positioning for the pattern P4 through a feedback control of the detecting section 17, 16. Therefore, after the positioning for the detecting sections 17, 16 has been completed, the circuit 21 performs a detailed comparison between the shapes of the patterns P3 and P4 to decide the acceptability concerning the quality of the patterns 4, 3. |
