J. Phys. IV France 11 (2001) Pr3-461-Pr3-466
Formation of cubic SiC nanocrystals by laser-assisted CVDY. Kamlag1, 2, A. Goossens2, I. Colbeck1 and J. Schoonman2
1 University of Essex, Aerosol Science Group, Department of Biological Sciences, Wivenhoe Park, Colchester CO4 3SQ. U. K.
2 Delft University of Technology, Laboratory for Inorganic Chemistry, Julianalaan 136, 2628 Delft, The Netherlands
Nanocrystals of cubic Silicon carbide (SiC) are formed using laser-assisted chemical vapor deposition. A CO2 laser beam is mechanically chopped to obtain pulsed infra-red excitation. Silane (SiH4) and acetylene (C2 H2) have been used as precursors. The formed SiC has the zinc-blende crystal phase (β-phase) with an average primary particle size of about 12 nm. As expected, higher chop frequencies yield smaller crystals. To establish electronic isolation between the particles, a native oxide shell of SiO2 can be formed by heating the particles in air. Subsequent etching with HF removes the oxide shell leading to further reduction of the particle size down to 4 nm.
© EDP Sciences 2001