Thermodynamics and Kinetics of SiC CVD Epitaxy

Abstract

One of the challenges in modeling epitaxial growth is to establish a connection between the experimental conditions and microstructure and epitaxial quality of the films. At the core of this problem is the need to have accurate models of the heterogeneous chemistry during epitaxy that can bridge reactor scale with atomic scale simulations and take into account the impact of film microstructure. In this work we focus on the heterogeneous chemistry models for SiC epitaxy by CVD. First, we carry out a sensitivity analysis of existing models in the literature, and we identify their limitations as well as the main reaction pathways that can be found at different experimental conditions. We then cast these models in the context of the step-flow growth. This allow us to rationalize the expected dependence of the different sticking probability values on the miscut angle and, more generally, on the surface terrace to step site ratio. Finally we show how these models can be used to bridge reactor-scale and atomistic simulations by providing sticking probabilities that depend on the surface morphology and the atomistic details of gas-surface interaction.