Toward a consistent and accurate approach to modeling projection optics

Abstract

This paper presents a consistent and modularized approach to modeling projection optics. Vector nature of light and polarization effect are considered from the very beginning at source, through mask and projection lens down into film stack. High-{NA} and immersion effect are also included. Of particular interest is the formulation of mask diffraction model that is pluggable, i.e. it can be a thin-mask model, a empirical approximate mask model, or rigorous mask 3D solver. We demonstrate that under Kirchoff thin-mask assumption our formulation is the same as Smythe formula. A compact film-stack model is formulated. The formulation is first presented in Abbe’s source integration approach and then reformulated in Hopkins’ {TCC} approach which allows for a {SVD} decomposition and are computationally more efficient for fixed optical setting.