Advanced jog handling techniques in MPC for better QoR

Designs which are output by OPC (Optical Proximity Correction) tools contain a large number of jog edges. Jogs are small edges introduced by OPC tools to create segments in an input design edge to provide freedom to the individual segments to move independently. Such segmentation is important to achieve correct, uniform results across the critical dimensions of a feature. Traditionally, Mask Process Correction (MPC) tools which work on OPC output, choose to not move these jog edges (a.k.a. jog freeze). The main reason for doing so is that the jog edges are so small that moving them does not significantly improve the mask quality. However, for newer design nodes, increasing OPC complexity results in primary segments similar in size to jog edge size. Hence, freezing the jogs may not be a viable option as it may mean that a significant portion of design edges are frozen. In this paper, we propose methods for movement of the jog edges and the impact it has on the overall mask quality. Shot count of the mask data post-fracture is an important Quality of Results (QoR) metric for Vector Shaped Beam (VSB) mask writer tools. One of the main advantages that comes from the flexibility of moving jog edges is to improve the mask data shot count. This paper will discuss the shot count improvement method within the MPC tool and show the impact it has on the other quality metrics.