| 摘要 |
PURPOSE:To enable to perform an inspection in a highly accurate manner by a method wherein, when positioning accuracy is detected using a vernier pattern, a laser beam is made to irradiate in a scanning manner on the surface whereon a pattern is superposed, the signal coming from the edge of the pattern is selected by the difference in intensity of the reflected light of said laser beam, and the amount of positional deviation is found by making a calculation. CONSTITUTION:The semiconductor wafer 4 having a vernier pattern on the surface is placed on a stage 5, and a lser beam is made to irradiate on the vernier pattern through the intermediary of a lense 3. Then, the light reflected from the edge of the pattern is detected by a lser detector 6, and this output is amplified by an amplifier 7. Said detector 6 and the amplifier 7 are built in an instrumental part 9, and the output coming from the instrumental part 9 is sent to the CPU containing a memory 11 and arithmetic operational parts. Subsequently, the result of the above operation is added to an interface 14 through the intermediary of an input-output control part 13, it is led back to the instrumental part 9, and the data of the input-output control part 13 is indicated on a indicating part 15. Through these procedures, the minimum value of the amount of deviation of pattern can be read out. |
