Patent ID: 6963394

Claim:
An inspecting device for a semiconductor wafer comprising: a holding unit which holds a wafer; a rotating unit which rotates the wafer by rotating the holding unit; an aligner unit which optically detects a cutout position and a center position of the wafer rotated by the rotating unit and obtains position determining data of the wafer; an observing unit for magnifying and observing fine patterns on the wafer, wherein the observing unit includes a camera portion for photoelectrical capture and is disposed at a position where the wafer held by the holding unit can be observed; a moving unit which relatively moves the holding unit with respect to the observing unit in an X-Y direction so as to keep a plane of the wafer at a same level; a control unit which controls the moving unit and the rotating unit to move and rotate the holding unit so as to position a mask ID of the wafer at a predetermined position within an observation field of the observing unit based on the obtained position determining data; and judging means for judging whether the mask ID of the wafer is appropriate by comparing image data which is photoelectrically captured by the camera portion and processed with stored reference image data of a mask ID.