Growth, etching, and doping features of SiC-CVD in a horizontal hot-wall reactor were numerically analyzed using the improved heterogeneous model. The improved model was able to explain the growth and etching features accurately. In addition, we propose the surface flux, surface carbon and silicon concentration, and its ratio as the universal parameter of the SiC-CVD process. Concerning doping features, the improved model showed that nitrogen and aluminum doping incorporation could be explained by the site competition model, while taking into account the amount of surface silicon and surface carbon, respectively.