Patent ID: 7461367
Filing Date: 2008-12-02
Classification: G03F

Abstract:
1. A method for modifying a plurality of merged sub-resolution assist features, comprising: receiving a mask pattern comprising a plurality of merged sub-resolution assist features forming a T shape, the plurality of merged sub-resolution assist features comprising a first segmenting sub-resolution assist feature intersecting a second segmenting sub-resolution assist feature at an intersection; representing each sub-resolution assist feature by an axis of the each sub-resolution assist feature to yield a plurality of axes; establishing that a segmenting axis of the plurality of axes is sufficiently long, the segmenting axis representing the first segmenting sub-resolution assist feature, wherein establishing that the segmenting axis of the plurality of axes is sufficiently long further comprises: establishing that a length of the segmenting axis is greater than or approximately equal to a sum comprising: removing a part of the segmenting axis, the part proximate to the intersection; and converting each axis to a sub-resolution assist feature to yield a plurality of modified merged sub-resolution assist features.