The epitaxial growth of 3C-SiC films on Si(100) substrates is demonstrated using a two-step chemical vapor deposition (CVD) process. A thin (50 nm) SiC buffer layer grown at 925 °C using 1,3-disilabutane is shown to enable the growth of a high crystalline quality epitaxial 3C-SiC film using methyltrichlorosilane at 1200 °C. The ability to deposit high-quality epitaxial film is traced to the suppression of void defects and to the improvement in film adhesion obtained by the deposition of the buffer layer at low temperature.