APPEARANCE INSPECTING DEVICE OF LSI WAFER

摘要

PURPOSE:To automate the inspection improving the reliability of the inspection by a method wherein one point on the surface of a wafer is irradiated with laser beam to detect any scattering beams emitted from a circuit pattern on the surface for comparing the detected image with design data to judge any discrepancy as a defect. CONSTITUTION:An LSI wafer 1 as an item to be inspected is placed on an X-Y table 7 to make a memory 3 memorize the design data of the surface layer to be inspected. The X-Y table 7 is driven for scanning by a front driving device while irradiating the wafer 1 with S polarized laser beam utilizing an illuminator 19. The circuit pattern on the topmost layer is exposed under no influence of the circuit pattern on the lower layer by means of making the incident angle of laser beams almost 90 deg.. The scattering beams from the circuit pattern of the surface layer of the wafer 1 are inputted in a photoelectric converter 17 through the intermediary of an objective lens 13 to compare the output from the photoelectric converter 17 with the design data memorized by the memory 3 for judging any defect and the signal concerning the defect may be successively inputted in a defective coordinate table 5.