Simulations of SiC CVD - Perspectives on the Need for Surface Reaction Model Improvements

Abstract

Simulations of SiC chemical vapor deposition is an excellent tool for understanding, improving and optimizing this complex process. However, models used up to date have often been validated for one particular set of process parameters, often in the silicon limited growth regime, in one particular growth equipment. With chlorinated precursors optimal growth condition is often found to take place at the border between carbon limited and silicon limited regimes. At those conditions the previous models fail to predict deposition rates properly. In this study we argue that molecules like C2H2, C2H4and CH4, actually might react with the surface with much higher rates than suggested before. Comparisons are made between the previous model and our new model, as well as experiments. It is shown that higher reactivities of the hydrocarbon molecules will improve simulation results as compared to experimental findings, and help to better explain some of the trends for varying C/Si ratios.