Impact of modelisation pixel size on OPC consistency

Franck Foussadier; Emek Yesilada; Jean-Christophe Le Denmat; Yorick Trouiller; Vincent Farys; Frédéric Robert; Gurwan Kerrien; Christian Gardin; Loic Perraud; Florent Vautrin; Alexandre Villaret; Catherine Martinelli; Jonathan Planchot; Jean Luc Di-Maria; Mazen Saied; Mame Kouna Top

doi:10.1117/12.814047

Translator Disclaimer

16 March 2009 Impact of modelisation pixel size on OPC consistency

Franck Foussadier, Emek Yesilada, Jean-Christophe Le Denmat, Yorick Trouiller, Vincent Farys, Frédéric Robert, Gurwan Kerrien, Christian Gardin, Loic Perraud, Florent Vautrin, Alexandre Villaret, Catherine Martinelli, Jonathan Planchot, Jean Luc Di-Maria, Mazen Saied, Mame Kouna Top

Author Affiliations +

Proceedings Volume 7274, Optical Microlithography XXII; 727416 (2009) https://doi.org/10.1117/12.814047
Event: SPIE Advanced Lithography, 2009, San Jose, California, United States

Abstract

In advanced technology nodes, due to accuracy and computing time constraint, OPC has shifted from discrete simulation to pixel based simulation. The simulation is grid based and then interpolation occurs between grid points. Even if the sampling is done below Nyquist rate, interpolation can cause some variations for same polygon placed at different location in the layout. Any variation is rounded during OPC treatment, because of discrete numbers used in OPC output file. The end result is inconsistency in post-OPC layout, where the same input polygon will give different outputs, depending on its position and orientation relative to the grid. This can have a major impact in CD control, in structures like SRAM for example, where mismatching between gates can cause major issue. There are some workarounds to minimize this effect, but most of them are post-treatment fix. In this paper, we will try to identify and solve the root cause of the problem. We will study the relationship between the pixel size and the consistency of post OPC results. The pixel size is often set based on optical parameters, but it might be possible to optimize it around this value to avoid inconsistency. One can say that the optimization will highly depend on design and not be possible for a real layout. As the range of pitch used in a design tends to decrease, thanks to fix pitch layouts, we may optimize pixel size for a full layout.

Citation Download Citation

Franck Foussadier, Emek Yesilada, Jean-Christophe Le Denmat, Yorick Trouiller, Vincent Farys, Frédéric Robert, Gurwan Kerrien, Christian Gardin, Loic Perraud, Florent Vautrin, Alexandre Villaret, Catherine Martinelli, Jonathan Planchot, Jean Luc Di-Maria, Mazen Saied, and Mame Kouna Top "Impact of modelisation pixel size on OPC consistency", Proc. SPIE 7274, Optical Microlithography XXII, 727416 (16 March 2009); https://doi.org/10.1117/12.814047

ACCESS THE FULL ARTICLE