Patent ID: 6649309
Filing Date: 2003-11-18
Classification: G03F

Abstract:
A method for correcting proximity errors in a lithographic process comprising the steps of:providing at least one curved shape to approximate the contour of a polygon on said mask, said polygon controlling the contour of said at least one curved shape; assigning to each side of said polygon at least one edge segment representing the shape of said polygon side; forming corners of said polygon by intersection of adjacent and non-colinear sets of said edge segments; assigning to each of said edge segments and to each of said corners a radius of curvature; assigning to each of said radii of curvature a maximum allowable limit from predetermined minimum and maximum values; and iteratively modifying said radii of curvature of each side and corner of said polygon until said maximum allowable limit is reached, wherein said at least one curved shape reaches the shape of the original polygon.