Patent ID: 7943274
Filing Date: 2011-05-17
Classification: G03F

Abstract:
1. A mask pattern correction method, comprising: an off-axis illumination light source wherein the off-axis illumination light source comprises a plurality of pupils respectively disposed on a first and second axis; providing an original layout, wherein the original layout comprises a plurality of device patterns; performing a correction process on the device patterns to correspondingly form a plurality of simulated patterns; analyzing the simulated patterns to select a plurality of unsaturated patterns from the simulated patterns; and exclusively rotating the device patterns in the original layout only one time corresponding to the unsaturated patterns without rotating the device patterns in the original layout again; wherein each of the rotated device patterns comprises a first set of opposite parallel edges and a second set of opposite parallel edges, and a first projection of the first axis projecting on a first plane on which the device patterns are located is perpendicular to the first set of opposite parallel edges of each of the rotated device patterns and a second projection of the second axis projection on the first plane is perpendicular to the second set of opposite parallel edges of each of the rotated device patterns.