METHOD OF INSPECTING DEFECTS IN CIRCUIT PATTERN AND SYSTEM FOR CARRYING OUT THE METHOD

A circuit pattern to be inspected is imaged so that an image signal representing the circuit pattern to be inspected is produced. The image signal of the circuit pattern is compared with a reference circuit pattern image signal, wherein a part of the image signal discerned to be different from the latter is detected as a candidate defect, at a rate synchronized with the rate of imaging. A local image signal corresponding to each local image covering a region including every one of detected candidate defects is extracted and stored in a memory device. Thereafter, on the basis of the local image signal read out from the memory device, whether or not the candidate defect concerned is fatally harmful with regard to electrical conductivity is examined at a rate asynchronous with the imaging rate.