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 (1?1?1?) and (111?) planes.