Epitaxial beta-SiC thin films were successfully grown on carburized Si(100) substrates using bis-trimethylsilylmethane (BTMSM) as an organo-silicon precursor at deposition temperatures as low as 1100 degrees C. TEM analysis revealed that the carburized buffer layer was not a single crystal but well-aligned polycrystals. Very smooth and high quality single crystal films were obtained at 4.8 x 10(4) Pa. The defect density of the beta-SiC thin films deposited to 5 mu m thickness using BTMSM was as low as that of other commercial films deposited using gas sources. It appears that the carburized buffer layer, which was partially polycrystalline, reduces the out-diffusion of the free Si species from the substrate.