| 摘要 |
PURPOSE:To realize the pattern recognition of high precision by hue-separating reflected light from two or ore fine patterns overlapped with >=2 patterns into the ratio at every constituent primary color, and comparing each hue element with a threshold. CONSTITUTION:Photographed pictures in matrix coordinates corresponding to wafers 3 and 4 are obtained by color sensors 5a, 5b. The obtained photographed picture is separated into R, G and B signals, and they are inputted to a first comparator group 7a to 7c in a signal comparing control part 6. Here, R, G and B signals are compared respectively, and the differences of their hue components are outputted as a differential signals to a second comparator group 8a to 8c. The comparator group 8a to 8c compares the difference signals with the threshold set previously in the control part 6, and when they exceed this, they are outputted as pattern defect signals to a data processing part 10, and the processing part 10 decides the quality of the pattern. |
