In this paper we will evaluate the impact of stitching on process window and show how EDA can help to improve the manufacturability of stitched layers. More specifically, we demonstrate modeling of double exposure effects suitable for full-field correction and verification that incorporates aerial image cross-talk, optical black border transitions, subresolution gratings, sub-resolution assist-features and long-range flare. We also evaluate how stitching impacts different high NA processes and how correction of these effects (ex. via optical proximity correction, inverse lithography technology) can be used to increase process robustness. Finally, we examine the impact of stitched pattern overlap to process window and how loss of process window due to stitching can be mitigated.
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