Patent ID: 8759762

Claim:
A method of inspecting for plug-to-plug short defects on a sample of a semiconductor device by charged particle beam imaging where a charged particle beam is repeatedly line-scanned over said sample with a line-to-line advancement direction perpendicular to the line-scan direction, comprising: scanning said sample with line-to-line advancement along a first horizontal direction for obtaining a first grey level image of said sample; scanning said sample with line-to-line advancement along a second horizontal direction for obtaining a second grey level image of said sample, wherein said first grey level image and said second grey level image represent grey levels of a plurality of plug patterns on said sample; identifying abnormal plug patterns by identifying abnormal grey levels on said first grey level image and said second grey level image; and comparing said abnormal plug patterns in said first grey level image and said second grey level image to locate a plug-to-plug short defect on said sample.