High uniform N-type doping of 4H-SiC homoepitaxy based on a horizontal hot-wall reactor

Abstract

A multi-physical coupling mathematical model of the reaction chamber was established based on a horizontal hot-wall SiC epitaxial reactor. Simulations were conducted to analyze the distribution characteristics of the temperature and flow field in the chamber. Subsequently, a series of process experiments were designed to systematically investigate the impact of key process parameters such as C/Si ratio, growth temperature, and carrier H₂ flow rate on the doping concentration and its distribution of 6-inch N-type 4H-SiC homoepitaxy. The relationships between these main process parameters and phenomena such as “site-competition epitaxy”, “loss along the path” and “W-shaped” doping distribution were analyzed comprehensively. By combining simulation results with experimental analysis, optimal epitaxial process parameters were determined, resulting in a significant improvement in doping uniformity to 2.7 % and the preparation of high-quality epitaxial wafer, surpassing industry standards.