Modeling of mask diffraction and projection imaging for advanced optical and EUV lithography

Lithographic masks are an important and increasingly complex part of systems for advanced optical and extreme ultraviolet (EUV) lithography. They introduce polarization and phase effects with a significant impact on the entire system performance. Rigorous electromagnetic field (EMF) modeling of the mask is indispensable for a predictive simulation of lithographic processes. This paper describes several alternative mask models and their integration into a lithography simulation framework. Several examples demonstrate the relevance of an accurate mask diffraction modeling for the prediction of the lithographic process performance.