SiC–SiO2 nanocomposite films prepared by laser CVD using tetraethyl orthosilicate and acetylene as precursors

SiC–SiO2 nanocomposite films were prepared by laser chemical vapor deposition (LCVD) using a CO2 laser with tetraethyl orthosilicate (TEOS) and acetylene (C2H2) as precursors. The effects of laser power on the crystal phase and microstructure of the SiC–SiO2 nanocomposite films were investigated. Films produced with laser power below 150 W (below 1523 K) had an amorphous structure, while those produced above 200 W (above 1673 K) were a mixture of crystalline SiC and amorphous phase. At 245 W (1774 K) the film contained 3C-SiC nanocrystals 100 to 200 nm in diameter dispersed in an amorphous matrix having high-density stacking faults formed on the (1̄1̄1̄) and (111̄) planes.