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Crystallization Kinetics of Fe-DOPED A1203

Published online by Cambridge University Press:  15 February 2011

Todd W. Simpson
Affiliation:
Department of Physics, University of Western Ontario, London, Ontario, N6A 3K7
Ian V. Mitchell
Affiliation:
Department of Physics, University of Western Ontario, London, Ontario, N6A 3K7
Ning Yu
Affiliation:
Los Alamos National Laboratory, Division of Materials Science and Technology, Los Alamos, NM, 87545
Michael Nastasi
Affiliation:
Los Alamos National Laboratory, Division of Materials Science and Technology, Los Alamos, NM, 87545
Paul C. Mcintyre
Affiliation:
Los Alamos National Laboratory, Division of Materials Science and Technology, Los Alamos, NM, 87545
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Abstract

Time resolved optical reflectivity (TRR) and Rutherford backscattering spectrometry (RBS) and ion channelling methods have been applied to determine the crystallization kinetics of Fe-doped A1203 in the temperature range of 900-1050°C. Amorphous A1203 films, approximately 250 nm thick and with Fe cation concentrations of 0, 1.85, 2.2 and 4.5%, were formed by e-beam deposition on single crystal, [0001] oriented, A1203 substrates. Annealing was performed under an oxygen ambient in a conventional tube furnace, and the optical changes which accompany crystallization were monitored, in situ, by TRR with a 633nm wavelength laser.

Crystallization is observed to proceed via solid phase epitaxy. An intermediate, epitaxial phase of -γ-Al203 is formed before the samples reach the ultimate annealing temperature. The 5% Fe-doped film transforms from γ to α-A1203 at a rate approximately 10 times that of the pure A1203 film and the 1.85% and 2.2% Fe-doped films transform at rates between these two extremes. The Fe-dopants occupy substitional lattice sites in the epilayer. Each of the four sets of specimens displays an activation energy in the range 5.0±0.2eV for the γ,α phase transition.

Type
Research Article
Copyright
Copyright © Materials Research Society 1995

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References

[1] White, C.W., Boatner, L.A., Sklad, P.S., McHargue, C.J, Rankin, J., Farlow, G.C. and Aziz, M.J., Nucl. Instr. Meth. B32, (1988) 11 Google Scholar
[2] Hoven, G.N. Van den, Snoeks, E., Polman, A., Uffelen, J.W.M. van, Oei, Y.S. and Smit, M.K., Appl. Phys. Lett. 62, (1993) 3065 Google Scholar
[3] Yu, N. and Nastasi, M., Appl. Phys. Lett. 65 (2) (1994) 180 Google Scholar
[4] McCallum, J.C., Simpson, T.W. and Mitchell, I.V., Nucl. Instr. Meth, B91 (1994) 60 Google Scholar