Optimization of a buffer layer for cubic silicon carbide growth on silicon substrates

摘要

A procedure for the optimization of a 3C-SiC buffer layer for the deposition of 3C-SiC/(001) Si is described. After a standard carbonization at 1125 ℃, SiH_4 and C_3H_8 were added to the gas phase while the temperature was raised from 1125 ℃ to the growth temperature of 1380 ℃ with a controlled temperature ramp to grow a thin SiC layer. The quality and the crystallinity of the buffer layer and the presence of voids at the SiC/Si interface are related to the gas flow and to the heating ramp rate. In order to improve the buffer quality the SiH_4 and C_3H_8 flows were changed during the heating ramp. On the optimized buffer no voids were detected and a high-quality 1.5 μm 3C-SiC was grown to demonstrate the effectiveness of the described buffer.