Model-based adaptive fragmentation

Rule-based fragmentation has been used for many years in Optical Proximity Correction (OPC). It breaks the edge of polygons into small pieces according to the pre-defined rule based on the topography and context before model-based OPC. Although it works well in most case, it can not place the fragment point onto the proper position which decided by inherent Optical and process requirement sometimes. In this paper, an adaptive fragmentation is proposed. The polygon is first dissected according to the traditional rule. In the following iteration, the edge is re-fragmented, in which some fragments are deleted and some new fragments are created, according to their image properties. Using this method, the dissection point can be placed in the right position. It can improve the correction accuracy and eliminate the unwanted fragment at the same time.