Patent ID: 6879719

Claim:
A method of extracting two-dimensional image shapes of submicron structures formed by photolithography on semiconductor wafers, from a two-dimensional array of pixel data, the method comprising the steps of: using a photolithography process to form a submicron structure on a semiconductor wafer; forming an electron beam image of said structure on a two-dimensional array of pixels, wherein said images has a shape; identifying a preliminary, approximate edge image shape; identifying a more precise edge of the image shape by a) identifying a point along said approximate edge, b) obtaining intensity vs. pixel information along a plurality of scans extending in different directions, through substantially said point, in the vicinity of the edge of the image shape; c) recognizing scans with sufficient contrast as containing edge information; d) subjecting the recognized scans to an edge detection algorithm; e) detecting a point on the more precise edge location of the image by using said edge detection algorithm; and f) repeating steps b), c), d) and e) for different points along the approximate edge to generate a locus of points that define the two-dimensional shape of the image from the detected edge values.