Coupling reactor and feature scale models

Abstract

Summary form only given. Plasma transport/chemistry models have made significant strides in the last decade and are currently being used to analyze and optimize plasma reactors used in the semiconductor processing industry. Feature scale models have been used to study profile evolution and charging resulting from plasma processing. Linking reactor and feature scale models is important given their effect on each other. In particular, the non-uniformity of the plasma across the wafer causes differences in the evolution of the feature profiles across the wafer. On the other hand, the topography of the features on the wafer surface impact the sheath profile, charging, and outgassing from the surface which affects the plasma on the reactor scale. A Monte Carlo (MC) model for the sheath and the pre-sheath regions in a plasma has been developed. This MC (pre-)sheath model has been integrated into a reactor scale model (CFD-ACE+) and coupled to feature scale models (SPEEDIE and CATS). The coupling method and (pre-)sheath models are contrasted with currently available models. The reactor/sheath/feature scale model is applied to plasma etch of silicon using a Cl chemistry. The effect of plasma power and flow rates on profile evolution, etch rate, and charging rate at the feature scale is discussed.