Synopsys, Inc.
Producing mask layouts with rounded corners

Abstract:

A two-dimensional representation of a polygon is converted to a parametric representation. A smoothing filter is applied to the parametric representation to produce corner rounding. In some embodiments, a polygon layout plus a model that specifies how much corner rounding should be applied are taken as inputs. The desired amount of rounding to the corners in the input polygons is applied and this produces a new polygon layout with corners that are properly rounded as its output. The process can be implemented so that it does not induce any pattern-size dependent bias. It also can be designed so that it does not induce line-end pullbacks. However, this feature can be turned off if line-end pullbacks are deemed appropriate for the specific application.