| 摘要 |
PROBLEM TO BE SOLVED: To accurately recognize the state of each treating device by detecting the occurring states of defects on a substrate to be treated and discriminating the kinds and positions of the detects before and after a prescribed process and discriminating the criticalness of the defects based on the outputs obtained from the detection and discrimination. SOLUTION: A TV camera 13 detects a circuit pattern on a wafer 1 irradiated with light from a Xe lamp 12 in an enlarging state through an objective lens 3 and an A/D converter 14 digitizes the output of the camera 13. The defect of the pattern is discriminated by comparing the detected image with the last chip picture stored in an image memory 15a. The image detection and defect discrimination are repeated and, when a defect is detected, the inspections are interrupted and the multifocal images of the defective part and corresponding acceptable part are detected. Then the difference image between the multifocal images and maximum values of the images are detected and the detect is classified into foreign matters, discoloration, and shape defect. When the defect is classified into foreign matters, the coordinates of the defect are stored and the criticalness of the foreign matters is discriminated by again detecting and classifying the defect after the wafer is passed through the next device. |
