High-quality homoepitaxial layers grown on 4H-SiC at a high growth rate by vertical LPCVD

High quality, homoepitaxial layers of 4H-SiC were grown on off-oriented 4H-SiC (0001) Si planes in a vertical low-pressure hot-wall CVD system (LPCVD) by using trichlorosilane (TCS) as a silicon precursor source together with ethylene (C2H4) as a carbon precursor source. The growth rate of 25-30 mu m/h has been achieved at lower temperatures between 1500 and 1530 degrees C. The surface roughness and crystalline quality of 50 mu m thick epitaxial layers (grown for 2 h) did not deteriorate compared with the corresponding results of thinner layers (grown for 30 min). The background doping concentration was reduced to 2.13 x 10(15) cm(3). The effect of the C/Si ratio in the gas phase on growth rate and quality of the epi-layers was investigated.