11 May 2009 Model-based assist features
Author Affiliations +
Proceedings Volume 7379, Photomask and Next-Generation Lithography Mask Technology XVI; 73792Z (2009) https://doi.org/10.1117/12.824350
Event: Photomask and NGL Mask Technology XVI, 2009, Yokohama, Japan
We present a model-based method of generating and optimizing sub-resolution assist features. Assist feature generation is based on a focus sensitivity map derived from a cost function that minimizes the variations in the printed pattern with respect to focus change. We also demonstrate a method to generate mask-friendly SRAF polygons from the focus sensitivity map. After model-based placement, assist features and the main polygons are optimized together by moving their edge segments. One of the optimization goals is that side-lobes and assist features should not print. This is enforced by computing image on a two dimensional grid. We demonstrate the process window improvement for a contact layer example.
© (2009) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Bayram Yenikaya, Bayram Yenikaya, Oleg Alexandrov, Oleg Alexandrov, Steven Chen, Steven Chen, Anwei Liu, Anwei Liu, Ali Mokhberi, Ali Mokhberi, Apo Sezginer, Apo Sezginer, } "Model-based assist features", Proc. SPIE 7379, Photomask and Next-Generation Lithography Mask Technology XVI, 73792Z (11 May 2009); doi: 10.1117/12.824350; https://doi.org/10.1117/12.824350

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