Patent ID: 7853918

Claim:
A method of inserting dummy patterns, the method comprising: providing a window area comprising a main pattern, wherein the main pattern comprises first patterns of a first type of features, and second patterns of a second type of features, and wherein the first and the second types are different types; globally inserting first dummy patterns throughout the window area, wherein the first dummy patterns are dummy patterns of the first type of features; enlarging the main pattern to generate an enlarged main pattern, wherein the enlarged main pattern occupies an enlarged region of the window area; removing an entire portion of the first dummy patterns in the enlarged region from the first dummy patterns to generate first inversed dummy patterns; combining the first patterns in the main pattern with the first inversed dummy patterns to generate first mask patterns for the first type of features, wherein at least one of the steps of globally inserting the first dummy patterns, enlarging the main pattern, removing the entire portion of the first dummy patterns, and combining the first patterns is performed by a design tool; and taping-out a graphic data system (GDS) file comprising the first mask patterns.