Patent ID: 7596776
Filing Date: 2009-09-29
Classification: G06F

Abstract:
1. A light intensity distribution simulation method for predicting an intensity distribution of light on a substrate when a photomask comprising a pattern is irradiated with light in which a shape distribution of an effective light source is defined, by using an illumination optical system, and the light which passes through the photomask is projected on the substrate through a projection optical system, the method comprising: extracting a plurality of point light sources from the shape distribution of the effective light source; entering light in the pattern of the photomask, the light being emitted from each of the plurality of point light sources; calculating an effective shape for each of the plurality of point light sources by a CPU, the effective shape being a shape obtained by excluding a part from a design shape of an aperture of the pattern, the part being failed to be irradiated with the light directly due to a sidewall of a pattern film including the pattern; and calculating a distribution of diffraction light generated in the pattern for each of the plurality of point light sources by a CPU by using the effective shape calculated for each of the plurality of point light sources.