Patent ID: 8028253

Claim:
A computer-executed method for determining mask layouts, the method comprising: identifying a set of critical edges in a design intent, wherein the set of critical edges is desired to be printed using a trench-split based multiple patterning process which prints opposing edges of a shape using different masks if the distance between the opposing edges is less than the minimum line width that can be printed using a single stage of the trench-split based multiple patterning process; creating a first set of mask shapes in a first mask layout for printing a first subset of critical edges in the design intent; creating a second set of mask shapes in a second mask layout for printing a second subset of critical edges in the design intent; in response to determining that a first mask shape in the first set of mask shapes does not abut a second mask shape in the second set of mask shapes, increasing, by computer, the first mask shape's size by a first increment; and in response to determining that the second mask shape does not abut the first mask shape, increasing, by computer, the second mask shape's size by a second increment.