Patent ID: 8563200

Claim:
A manufacturing method of a photomask for photoengraving predetermined patterns in a photosensitive material film over a semiconductor substrate, the method comprising the steps of: in a desired pattern with designed values, extracting proximity design features that are close to each other and will brought closer to each other when optical proximity correction is carried out, and are estimated not to be stably resolved as a photomask pattern and to violate a mask rule check; in the proximity design features, setting correction prohibited regions where optical proximity correction is not carried out, based on the distance between the features obtained from the extracted proximity design features and a resolution obtained from the wavelength of the exposure light and the numerical aperture of an exposure device; carrying out optical proximity correction on the proximity design features with the correction prohibited regions excluded to obtain corrected proximity patterns; and carrying out electron beam lithography based on the corrected proximity patterns and thereby patterning a predetermined mask material.