J. Phys. IV France 05 (1995) C5-967-C5-974
Low Pressure CVD of Tungsten CarbidesP. Tägtström, H. Högberg, U. Jansson and J.-O. Carlsson
Thin Film and Surface Chemistry Group, Department of Inorganic Chemistry, University of Uppsala, Box 531, 751 21 Uppsala, Sweden
Tungsten carbide films have been deposited by CVD from a WF6/C3H8/H2 gas mixture on several different substrate materials (Ta, Si, SiC and C). Single-phase WC films could easily be obtained on Ta substrates at 900°C using a total pressure of 100 mTorr and a high linear gas flow velocity (7 m/s). It was found that the low pressures favoured the growth of carbon-rich films and made the deposition zone for WC longer. The phase composition of the films and deposition rates were also strongly affected by the substrate material. The substrate dependence was attributed to the chemical reactivity of WF6.
© EDP Sciences 1995