Fast and accurate 3D mask model for full-chip OPC and verification

摘要

A new framework has been developed to model 3D thick mask effects for full-chip OPC and verifications. In addition to electromagnetic (EM) scattering effects, the new model also takes into account the non-Hopkins oblique incidence effects commonly found in real lithography systems but missing in prior art. Evaluations against rigorous simulations and experimental data showed the new model provides improved accuracy, compared to both the thin-mask model and the thick-mask model based on Hopkins treatment of oblique incidence.