Growth of Crystalline Tungsten Carbides Using 1,1,3,3-Tetramethyl-1,3-disilacyclobutane on a Heated Tungsten Filament

2013 
A method of forming crystalline tungsten carbides was reported by exposing the heated tungsten filament to 1,1,3,3-tetramethyl-1,3-disilacyclobutane (TMDSCB) in a hot-wire chemical vapor deposition process. Methyl radicals produced from the decomposition of TMDSCB on the filament serve as the carbon source. The formation of tungsten carbides was investigated by X-ray diffraction, cross-sectional scanning electron microscopy, and in-situ filament resistance measurements. A pure W2C phase was formed at a high temperature of 2400 °C after 1–2 h exposure time with a growth rate of 4.4 μm min–1. The growth of the W2C layer is found to be a diffusion-controlled process. Our study at longer deposition time of 3–4 h shows that once the metal filament is fully carburized to form W2C, the carbon-rich WC phase starts to form on the outside layer upon further exposure to TMDSCB. A WC layer with no contamination from the W2C phase was found to be formed at 2400 °C and 4 h deposition time.
    • Correction
    • Source
    • Cite
    • Save
    • Machine Reading By IdeaReader
    39
    References
    13
    Citations
    NaN
    KQI
    []