Patent ID: 6811935
Filing Date: 2004-11-02
Classification: G03F

Abstract:
A method, comprising:identifying a pattern for a layer to be formed using a photolithographic mask, the pattern including a plurality of intersecting line segments defining an intersection with a plurality of corners; and laying out phase shift regions for the identified pattern to produce a phase shift mask, the phase shift mask having phase shift regions extending adjacent to line segments in the plurality of intersecting line segments and around the corners in the plurality of corners; identifying one corner of the plurality of corners according to a parameter related to relative process latitudes for the plurality of corners, and in said identified one corner, dividing the phase shift region into a first phase shift region having a first phase extending adjacent the line segment on one side of said identified one corner, and a second phase shift region having a second phase extending adjacent the line segment on the other side of said identified one corner; and laying out a complementary mask including an opaque feature preventing exposure of the plurality of intersecting line segments to be exposed using the phase shift mask, the opaque feature including a cut-out in said identified one corner to expose any feature resulting from the phase difference in said identified one corner between the first phase shift region and the second phase shift region.