Epitaxial monocrystalline SiC films grown on Si by HFCVD at 780°C

In this paper, our work is reported on heteroepitaxial monocrystalline SiC films deposited on single-crystalline (111) silicon by hot filament chemical vapor deposition (HFCVD) with a gas mixture of methane, silane and hydrogen at a low temperature of 780°C. The surface micrography and thickness of SiC films on Si (111) substrate were analyzed by scanning electron microscopy (SEM). The characteristics and crystallinity of the SiC film were examined by X-ray diffractometer (XRD), transmission electron microscopy (TEM) and auger electron spectrum (AES). The peaks of Si (111), SiC (111) and SiC (222) planes were observed on the X-ray diffraction spectrum, but not the peaks of the SiC (200) or SiC (220) planes. The diffraction pattern of TEM also indicates that the SiC films are single-crystalline structure. AES shows that the element ratio of silicon and carbon in the SiC film is 1:1.004. The preparation conditions were as follows: a filament temperature of 2100°C, substrate temperature of 780°C, hydrogen flow rate of 100 sccm, methane concentration of 8.0%, silane concentration of 1.0% and a reaction pressure of 150 Pa.