Dome-like and dense SiC-SiO2 nanocomposite films synthesized by laser chemical vapor deposition using CO2 laser

SiC-SiO2 nanocomposite films were prepared by laser chemical vapor deposition (LCVD) using a CO2 laser; tetraethyl orthosilicate and acetylene were used as precursors. An amorphous phase was formed at a deposition temperature below 1650 K, whereas a SiC (3 C) crystalline phase was co-deposited with amorphous SiO2 at a deposition temperature above 1650 K. Dome-like deposits were observed when low total pressure and high temperature were applied. At higher total pressure and lower temperature, the SiC-SiO2 nanocomposite film was obtained, with SiC grains about 10 nm in diameter distributed in amorphous SiO2. The highest deposition rate was 374 μm h− 1 at 1675 K and 400 Pa.