Patent ID: 6647543
Filing Date: 2003-11-11
Classification: G03F

Abstract:
A method for manufacturing a pair of complementary masks comprising the steps of extracting a plurality of pattern data from design data, distributing said pattern data to a pair of complementary mask data, and forming a pair of complementary masks based on said complementary mask data, said distributing step including the steps of;allocating either a first or a second sign to each of said pattern data to obtain an initial combination of signs; changing said sign of one or more element of initial combination to obtain a next combination, and calculating a sum data for said next combination by adding areas of said pattern data each having said first sign in said next combination while subtracting areas of said pattern data each having said second sign in said next combination; iterating said changing of said sign and said calculating of a sum data for said next combination, to obtain an optimum combination of said first and second signs providing a minimum of said sum data; and assigning said pattern data having first signs to one of said complementary mask data, and said pattern having said second signs to the other of said complementary mask data.