| 摘要 |
PURPOSE:To detect only a defect by overcoming the minute ruggedness of a pattern and the difference of line width, by aligning and comparing each layer between two chips, repeating the alignment and the comparison as for a dissidence part, and deciding the defect at every layer. CONSTITUTION:The output of a linear image sensor 5 is converted to a digital signal by an A/D converter 11, and inputted to an edge detecting circuit 15a and an image memory 14. By using the image memory, the pattern of an adjacent chip is compared and inspected by one image sensor. A position shift detecting circuit 18 detects the dissidence of a binarization pattern being the output of edge detecting circuits 15a, 15b. In an aligning circuit 20, an alignment is executed by shifting the output of delaying circuits 19a, 19b so that the dissidence amount becomes minimum. Also, in a gradient comparator 30, the gradients of brightness related to areas which become the dissidence by a coincidence erasing circuit are compared, the defect is decided, and the dissidence is outputted. Such circuits are connected serially by the number of pattern layers. |
