Patent ID: 7349575
Filing Date: 2008-03-25
Classification: G06T

Abstract:
1. A pattern inspection method comprising: the first setting step of setting as a first binarization threshold a value between a density value of a conductor and a density value of a base in a continuous tone image obtained by sensing an inspection work; the second setting step of setting as a second binarization threshold a value between the density value of the conductor and the first binarization threshold; the third setting step of setting as a third binarization threshold a value between the first binarization threshold and the density value of the base; the measurement step of measuring in advance from the inspection work a first line width of the conductor at the first binarization threshold, a second line width of the conductor at the second binarization threshold, and a third line width of the conductor at the third binarization threshold; the first binarization step of binarizing the continuous tone image on the basis of the second binarization threshold to generate a first pattern to be measured; the second binarization step of binarizing the continuous tone image on the basis of the third binarization threshold to generate a second pattern to be measured; the first correction step of correcting, on the basis of the first line width and the second line width, a first inspection threshold which is set in advance in correspondence with the first binarization threshold and used to detect a deficit or disconnection, so as to make the first inspection threshold correspond to the second binarization threshold; the second correction step of correcting, on the basis of the first line width and the third line width, a second inspection threshold which is set in advance in correspondence with the first binarization threshold and used to detect a projection or short circuit, so as to make the second inspection threshold correspond to the third binarization threshold; the step of obtaining an error amount between the first pattern to be measured and a master pattern serving as a reference; the first inspection step of comparing the error amount between the first pattern to be measured and the master pattern with the corrected first inspection threshold; the step of obtaining an error amount between the second pattern to be measured and the master pattern; and the second inspection step of comparing the error amount between the second pattern to be measured and the master pattern with the corrected second inspection threshold.