COMPARATIVE TEST OF PATTERN FOR SEMICONDUCTOR CIRCUIT, OR THE LIKE

PURPOSE:To enable to judge defects of the whole chips by a method wherein an wafer is comparatively tested by two times in total by performing the test respectively by one time from the directions making the angle of 90 degrees mutually. CONSTITUTION:When scanning in the direction B is finished to the whole surface of the wafer 1, the wafer 1 is rotated at 90 degrees by an wafer rotating device 12, the interval between detectors 2a, 2b is made to coincide with width of one side being different from the side of the chip coincided at the preceding test by operating a detector fine adjustment 10 according to control of a controlling circuit 7, scanning in the direction A is performed again, and defect detection results outputted from a defect detecting circuit 4 are stored in a defect memory unit 5b together with the positional information of a finely moving stage outputted from the controller 7. The results of defect judgement in regard to the whole of the chips to be tested are stored in a memory 14, the stored informations thereof are read by an output device 15 to be recorded, and when the recorded results thereof are inputted to a different selector or corrector, etc., sorting or correcting, etc., of excellent articles and inferior articles can be enabled.