High quality β-SiC films obtained by low-temperature heteroepitaxy combined with a fast carbonization step

The present paper describes a new low-temperature process for the deposition of crystalline cubic silicon carbide on [100] silicon using methylsilane as precursor. A substantial improvement of crystal quality was achieved by applying a special fast carbonization step based on ethylene diluted in argon. The influence of the buffer-layer growth conditions, the SiC film thickness, and the deposition temperature on crystal quality and surface morphology was studied using SEM, PDS, and X-ray diffraction. In comparison to SiC layers grown without a carbonization step the FWHM of the [200] reflex was reduced from 0.54° to 0.21°, the surface roughness from 350nm to 38nm and the defect density by a factor of 9. The state-of-the-art quality was proved by the comparison to commercial films from Cree Research Inc., presumably grown at considerably higher temperatures.