New model for focus-exposure data analysis

The paper introduces an improved, physics-based function for fitting lithographic data from focus-exposure matrices. Unlike simple polynomial functions, the coefficients of this equation offer physical insight into the meaning and nature of the data. Derivation of this equation from first principles of the physics of lithographic imaging is presented. Examples based on typical experimental data are shown and, the advantages of using a physics-based fitting function is described based on improved fitting and noise filtering.