Patent ID: 6223139
Filing Date: 2001-04-24
Classification: G03F

Abstract:
A method of simulating aerial images of large mask areas during the fabrication of a semiconductor integrated circuit silicon wafer comprising the steps of:defining mask patterns to be projected by an exposure system to create images of said mask patterns;calculating an optimum sampling interval;and an optimum sampling range for said exposure system, said optimum sampling interval and said optimum sampling range being directly proportional to .lambda., wherein .lambda. represents the wavelength of said exposure system, and inversely proportional to .sigma. and NA, wherein .sigma. and NA are respectively the partial coherence factor and the numerical aperture of said exposure system;generating a characteristic matrix describing said exposure system based on said optimum interval and said optimum sampling range;inverting said matrix to obtain eigenvalues and eigenvectors representing a decomposition of said exposure system;convolving said mask patterns with said eigenvectors;weighing the resulting convolution by said eigenvalues; andsumming up said weighted convolutions for generating a final set of said aerial images of said patterns to be replicated on said silicon wafer to form said semiconductor integrated circuit silicon wafer.