Chromium catalysed silicon nitridation
- 90 Downloads
Silicon powder compacts were fabricated with various amounts of chromium (0–5 at %) deposited onto the surface of the silicon powder by a solution-deposition process. These compacts were heated to several maximum temperatures in the range 1100–1250‡C in a flowing 10% H2/90% N2 atmosphere to evaluate the effect of the chromium content on the silicon nitridation. It was observed that silicon compacts containing 5 at % Cr were fully nitrided in approximately 3 h at 1150‡C, while less than 8% nitridation was achieved for pure-silicon compacts (with 0 at % Cr) compacts under the same conditions. Single-crystal silicon wafers with a 50 nm chromium layer were also nitrided; this provided a planar geometry, which facilitated our study of the catalysis mechanism. The rate-controlling process was shown to be first order, which may be indicative of a nucleation-and-growth mechanism, which is commonly observed for α-silicon-nitride formation. This work demonstrates the feasibility of producing reaction-bonded silicon nitride at low temperatures using chromium catalysis, and it indicates the potential for fabricating fibre-reinforced silicon-nitride composites containing thermally sensitive fibres.
KeywordsChromium Nitrided Silicon Wafer Silicon Nitride Catalysis Mechanism
Unable to display preview. Download preview PDF.
- 4.L. M. Sheppard (ed), “Ceramic source,” Vol. 8 (American Ceramic Society, Westerville, OH, 1992).Google Scholar
- 5.D. Messier and W. Croft, “Silicon Nitride,’ Prep. Prop. Solid State Mater. 7 (Marcel Dekker, New York, 1982) 131.Google Scholar
- 11.P. Popper and S. N. Ruddleson, Trans. Brit. Ceram. Soc. 60 (1961) 603.Google Scholar
- 16.C. P. Gazzara and D. R. Messier, Amer. Ceram. Soc. Bull. 56 (1977) 777.Google Scholar
- 17.C. G. Cofer, “Catalytic nitridation of silicon”, M. S. Thesis (University of Illinois at Urbana-Champaign, 1993).Google Scholar
- 19.S. P. Murarka, in “Silicides for VLSI applications” (Academic Press, New York, 1983).Google Scholar
- 20.J. R. Anderson and M. Boudart, (eds) “Catalysis science and technology” Vol. 1 (Springer-Verlag, New York, 1981).Google Scholar