Patent ID: 7769226

Claim:
A pattern inspection method using a processor to carry out the steps of: magnifying and taking a color image including a plurality of pixels, wherein the color image includes a contact hole over a substrate, and the contact hole occupies at least two of the plurality of pixels; generating first color information of each of the plurality of pixels, wherein the first color information includes three color coordinate components, red (R), green (G), and blue (B), of an RGB color space; converting the first color information of each of the plurality of pixels into second color information including first, second and third color coordinate components; generating a gray-scale image in accordance with the first color coordinate component; generating a binary image from the gray-scale image by regarding one of the plurality of pixels having a brightness of less than a predetermined threshold as black pixel and another one of the plurality of pixels having a brightness of more than the predetermined threshold as a white pixel; detecting the contact hole from the binary image to obtain coordinate data of at least two of the plurality of pixels occupied by the contact hole; calculating a mean value of the second color coordinate component of at least two of the plurality of pixels occupied by the contact hole; and comparing the mean value of the second color coordinate component in each contact hole with a preset non-defective reference color information.