Patent ID: 8793626

Claim:
A method of computational lithography, comprising: providing through-focus critical dimension (CD) curves at a range of different focus values (Bossung curves) for a plurality of feature types that include different ratios of line width to space width, and using software run on a computing device; determining if there is at least one marginal feature type from said plurality of feature types based an image tool capability and a predetermined process specification affected by at least one of said plurality of feature types; provided said marginal feature type is determined to be present, upsizing at least said marginal feature type, wherein a degree of said upsizing increases as a curvature of said Bossung curves increases, compiling a computational lithography model including said upsizing, wherein said upsizing comprises selecting said degree of said upsizing to center a mean of a distribution of a circuit parameter of a circuit element including said marginal feature type to obtain a target mean value for said circuit parameter.