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EBSD Analysis of Tungsten-Filament Carburization During the Hot-Wire CVD of Multi-Walled Carbon Nanotubes

Published online by Cambridge University Press:  15 January 2014

Clive J. Oliphant*
Affiliation:
Department of Physics, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa National Metrology Institute of South Africa, Private Bag X34, Lynwood Ridge, Pretoria 0040, South Africa
Christopher J. Arendse
Affiliation:
Department of Physics, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa
Sigqibo T. Camagu
Affiliation:
Council for Scientific and Industrial Research, Light Metals, Pretoria 0001, South Africa
Hendrik Swart
Affiliation:
Department of Physics, University of the Free State, Bloemfontein, 9300, South Africa
*
*Corresponding author. E-mail: [email protected]
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Abstract

Filament condition during hot-wire chemical vapor deposition conditions of multi-walled carbon nanotubes is a major concern for a stable deposition process. We report on the novel application of electron backscatter diffraction to characterize the carburization of tungsten filaments. During the synthesis, the W-filaments transform to W2C and WC. W-carbide growth followed a parabolic behavior corresponding to the diffusion of C as the rate-determining step. The grain size of W, W2C, and WC increases with longer exposure time and increasing filament temperature. The grain size of the recrystallizing W-core and W2C phase grows from the perimeter inwardly and this phenomenon is enhanced at filament temperatures in excess of 1,400°C. Cracks appear at filament temperatures >1,600°C, accompanied by a reduction in the filament operational lifetime. The increase of the W2C and recrystallized W-core grain size from the perimeter inwardly is ascribed to a thermal gradient within the filament, which in turn influences the hardness measurements and crack formation.

Type
Materials Applications
Copyright
Copyright © Microscopy Society of America 2014 

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References

Arendse, C.J., Malgas, G.F., Scriba, M.R., Cummings, F.R. & Knoesen, D. (2007). Effect of deposition pressure on the morphology and structural properties of carbon nanotubes synthesized by hot-filament chemical vapour deposition. J Nanosci Nanotechnol 7, 36383642.Google Scholar
Chen, X., Hasegawa, M., Yang, S., Nitta, Y., Katsuno, T. & Motojima, S. (2008). Preparation of carbon microcoils by catalytic methane hot-wire CVD process. Thin Solid Films 516, 714717.Google Scholar
Cojocaru, C.S., Kim, D., Pribat, D. & Bourée, J.E. (2006). Synthesis of multi-walled carbon nanotubes by combining hot-wire and dc plasma-enhanced chemical vapour deposition. Thin Solid Films 501, 227232.CrossRefGoogle Scholar
Davidson, C.F., Alexander, G.B. & Wadsworth, M.E. (1979). Catalytic effect of cobalt on the carburization kinetics of tungsten. Metall Trans A 10, 10591069.CrossRefGoogle Scholar
Dillon, A.C., Mahan, A.H., Parilla, P.A., Alleman, J.L., Heben, M.J., Jones, K.M. & Gilbert, K.E.H. (2003). Continuous hot wire chemical vapour deposition of high-density carbon multiwall nanotubes. Nano Lett 3, 14251429.Google Scholar
Kawale, S.S., Bhardwaj, S., Kshirsagar, D.E., Bhosale, C.H., Sharon, M. & Sharon, M. (2011). Thin films of carbon nanomaterial from natural precursor by hot-wire CVD. Fullerenes, Nanotubes, Carbon Nanostruct 19, 540549.Google Scholar
Knoesen, D., Arendse, C., Halindintwali, S. & Muller, T. (2008). Extension of the lifetime of tantalum filaments in the hot-wire (Cat) chemical vapour deposition process. Thin Solid Films 516, 822825.Google Scholar
Kromka, A., Janík, J., Šatka, A., Pavlov, J. & Červeň, I. (2001). Investigation of carburization of tungsten-carbide formation by hot-filament CVD technique. Acta Phys Slovaca 51, 359368.Google Scholar
Kurlov, A.S. & Gusev, A.I. (2006). Phase equilibria in the W-C system and tungsten carbides. Russ Chem Rev 75, 617636.Google Scholar
Langmuir, I. (1912). The dissociation of hydrogen into atoms. J Am Chem Soc 34, 860877.Google Scholar
Lassner, E. & Schubert, W. (1999). Tungsten: Properties, Chemistry, Technology of the Element, Alloys, and Chemical Compounds, pp. 18 and 20. New York: Kluwer Academic/Plenum Publishers.Google Scholar
Mahan, A.H., Carapella, J., Nelson, B.P., Crandall, R.S. & Balberg, I. (1991). Deposition of device quality, low H content amorphous silicon. J Appl Phys 69, 67286730.Google Scholar
McCarty, L.V., Donelson, R. & Hehemann, R.F. (1987). A diffusion model for tungsten powder carburization. Metall Trans A 18, 969974.Google Scholar
Moustakas, T.D. (1989). The role of the tungsten filament in the growth of polycrystalline diamond films by filament-assisted CVD of hydrocarbons. Solid State Ionics 3233, 861868.Google Scholar
Oliphant, C.J., Arendse, C.J., Malgas, G.F., Motaung, D.E., Muller, T.F.G., Halindintwali, S., Julies, B.A. & Knoesen, D. (2009a). Filament poisoning at typical carbon nanotube deposition conditions by hot-filament CVD. J Mater Sci 44, 26102616.Google Scholar
Oliphant, C.J., Arendse, C.J., Malgas, G.F., Motaung, D.E., Muller, T.F.G. & Knoesen, D. (2009b). Dual catalytic purpose of the tungsten filament during the synthesis of single helix carbon microcoils by hot-wire CVD. J Nanosci Nanotechnol 9, 58705873.Google Scholar
Oliphant, C.J., Arendse, C.J., Prins, S.N., Malgas, G.F. & Knoesen, D. (2012). Structural evolution of a Ta-filament during hot-wire chemical vapour deposition of silicon investigated by electron backscatter diffraction. J Mater Sci 47, 24052410.Google Scholar
Pryce Lewis, H.G., Bansal, N.P., White, A.J. & Handy, E.S. (2009). HWCVD of polymers: Commercialization and scale-up. Thin Solid Films 517, 35513554.Google Scholar
Shi, Y.L., Tong, L., Eustergerling, B.D. & Li, X.M. (2011). Silicidation and carburization of the tungsten filament in HWCVD with silacyclobutane precursor gases. Thin Solid Films 519, 44424446.Google Scholar
Tabata, A. & Niato, A. (2011). Structural changes in tungsten wire and their effect on the properties of hydrogen nanocrystalline cubic silicon carbide thin films. Thin Solid Films 519, 44514454.Google Scholar
van der Werf, C.H.M., Li, H., Verlaan, V., Oliphant, C.J., Bakker, R., Houweling, Z.S. & Schropp, R.E.I. (2009). Reversibility of silicidation of Ta filaments in HWCVD of thin film silicon. Thin Solid Films 517, 34313434.Google Scholar
Zeiler, E., Schwarz, S., Rosiwal, S.M. & Singer, R.F. (2002). Structural changes of tungsten heating filaments during CVD of diamond. Mater Sci Eng A 335, 236245.Google Scholar