| 摘要 |
PURPOSE:To simplify and speed up an inspection, by making movable one of optical systems provided in a pair being placed opposite to a sample, and by enabling the mutual comparison between different chips by changing a distance dimension between the two optical systems when any discord of patterns occurs. CONSTITUTION:Optical systems 6 and 7 are made opposite to the surface of a wafer 1 on an X-Y stage 4 after the optical-axis distance D between these systems is made to be in accord with a several-chip distance, and the wafer 1 is moved continuously in the X direction and in a stepping manner in the Y direction. The optical systems 6 and 7 scan the surface of the wafer 1 relatively and form the images of chip patterns on detectors 10 and 11 by objective lens 8 and 9 respectively, and chip pattern signals are outputted therefrom to signal processing circuits 18 and 19. Based on these signals, the processing circuits 18 and 19 deliver pattern recognition signals to a comparator circuit 20 which conducts the comparison between the two signals so as to determine an accord or a disaccord of the patterns, and the result of the determination is delivered from an output element 21. This constitution enables the checking of a pattern defect with respect to all of the chips on the wafer, thus enabling the inspection of an external appearance of any chip or wafer without complicating the structure of an inspecting apparatus. |
