Outdiffusion of the excess carbon in SiC films into Si substrate during film growth

The excess of C atoms diffused into the (111) Si substrate during the growth of the cubic SiC films are detected by Auger electron spectroscopy, infrared absorption, and x-ray photoelectron spectroscopy. The diffusion coefficient of the C atoms into the Si substrate at 820 °C is 8.4×10−15 cm2 s−1, which is close to the value of the diffusion of the C atoms into Si crystal using solid source. The C atoms mainly occupy substitutional sites in the Si substrate when the substrate temperature is below 750 °C, and both substitutional and nonsubstitutional sites when it is above 820 °C.