Patent ID: 6888958
Filing Date: 2005-05-03
Classification: G06T

Abstract:
1. A pattern inspection method comprising: comparing a real pattern window having real pattern data corresponding to predetermined pixels of the real pattern data obtained by imaging an inspection object to a design pattern window corresponding to the real pattern window and shifted design pattern windows which are obtained by shifting the design pattern windows in a plurality of directions, respectively, wherein a shift width of the shifted design pattern windows is within one pixel; selecting one window from the design pattern window and shifted design pattern windows; comparing a center pixel of the real pattern window to a center pixel of the selected design pattern window; and performing a pattern inspection of the inspection object, corresponding to the center pixel, according to a result of the comparison; wherein the performing comprises: obtaining a difference value by subtracting a noticed pixel of the selected one window and predetermined pixels surrounding the noticed pixel of the selected one window from a noticed pixel of the real pattern window and predetermined pixels surrounding the noticed pixel of the real pattern window, outputting 1) a “0” difference value in a case where the obtained difference value is within a difference value obtained by shifting the design pattern window by one pixel or less, 2) a difference value obtained by subtracting the minimum value from the obtained difference value in a case where the obtained difference value is less than a minimum value of difference values obtained by shifting the design pattern window and 3) a difference value obtained by subtracting a maximum value of difference values which are obtained by shifting the design pattern window by one pixel or less from the obtained difference value in a case where the obtained difference value is lager than the maximum value, and performing the pattern inspection of the inspection object by comparing the outputted difference value with a threshold value set in advance.