Post exposure bake (PEB) models in the lithography simulator SOLID-C have been extended in order to improve the description of kinetic and diffusion phenomena in chemically amplified resists. We have implemented several new models and options which take into account effects such as the diffusion of quencher base, different approaches to model the neutralization between photogenerated acid and a quencher base, spontaneous loss of quencher, and arbitrary dependencies of the diffusion coefficients on acid or inhibitor, respectively. In this study, the impact of these new model options on critical phenomena like iso-dense bias, linearity and line end shortening are examined. The simulations were performed for a calibrated KrF/ArF resist models.

Calibration of resist model parameters becomes more and more important in lithography simulation. The general goal of such a calibration procedure is to find parameters and model options which minimize the difference between experimentally measured and simulated data. In this paper a multidimensional downhill simplex method and a genetic algorithm are introduced. We investigate the performance of different modeling options such as the diffusivity of the photogenerated acid and of the quencher base, and different development models. Furthermore, new objective functions are proposed and evaluated: The overlap of process windows between simulated and experimental data and the comparison of linearity curves. The calibration procedures are performed for a 248 nm and for a 193 nm chemically amplified resist, respectively