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Aluminum Chemical Vapor Deposition Using Triisobutylaluminum: Mechanism, Kinetics, and Deposition Rates at Steady State

Published online by Cambridge University Press:  25 February 2011

Lawrence Dubois II
Affiliation:
AT&T Bell Laboratories, Murray Hill, New Jersey 07974.
Ralph G. Nuzzo
Affiliation:
AT&T Bell Laboratories, Murray Hill, New Jersey 07974.
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Abstract

An important step in the chemical vapor deposition (CVD) of aluminum from triisobutylaluminum (TIBA) is the reaction between TIBA (adsorbed from the gas phase) and the growing aluminum surface. We have studied this chemistry by impinging TIBA under collisionless conditions in an ultra-high vacuum system onto single crystal Al(111) and Al(100) substrates. We find that when TIBA (340K) collides with an aluminum surface heated to between 500 and 600K, the aluminum atom is cleanly abstracted from this precursor with near unit reaction probability to deposit, epitaxially, carbon-free aluminum films. The gas phase products are isobutylene and hydrogen. From monolayer thermal desorption experiments, we have determined the kinetic parameters for the rate-determining step, a β-hydride elimination reaction by surface bound isobutyl ligands. Using these kinetic parameters and a Langmuir absorption model, we can predict the rate of aluminum deposition at pressures ranging from 10−6 to 1 Torr.

Type
Research Article
Copyright
Copyright © Materials Research Society 1989

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References

REFERENCES

[1] Ziegler, K., Nagel, K. and Pfohl, W., Justus Liebigs Ann. Chem. 629, 210 (1960).Google Scholar
[2] Several studies of aluminum deposition from TIBA were reported. See, for example, Pierson, H. O., Thin Solid Films 45, 257 (1977).Google Scholar
[3] Cooke, M. J., Heinecke, R. A., Stem, R. C. and Maes, J. W. C., Solid State Technol. 25, 62 (1982).Google Scholar
[4] (a) Green, M. L., Levy, R. A., Nuzzo, R. G. and Coleman, E., Thin Solid Films 114, 367 (1984); (b) R. A. Levy, M. L. Green and P. K. Gallagher, J. Electrochem. Soc. 131, 2175 (1984); (c) C. G. Fleming, G. E. Blonder and G. S. Higashi, Mat. Res. Soc. Symp. Proc. 101, 183 (1988); (d) D. A. Mantell and T. E. Orlowski, Mat. Res. Soc. Symp. Proc. 101, 171 (1988).Google Scholar
[5] Bent, B. E., Nuzzo, R. G. and Dubois, L. H., Mat. Res. Soc. Symp. Proc. 101, 177 (1988).Google Scholar
[6] Bent, B. E., Zegarski, B. R., Nuzzo, R. G. and Dubois, L. H., in preparation.Google Scholar
[7] Bent, B. E., Nuzzo, R. G. and Dubois, L. H., J. Am. Chem. Soc. 111, 000 (1989).Google Scholar
[8] Dubois, L. H., Rev. Sci. Instrum. 60, 000 (1989).Google Scholar
[9] Collman, J. P., Hegedus, L. S., Norton, J. R. and Finke, R. G., Principles and Applications of Organotransition Metal Chemistry, 2nd Edition, University Science Books, Mill Valley, 386 (1987).Google Scholar
[10] Egger, K. W., J. Amer. Chem. Soc. 91, 2867 (1969); K. W. Egger, Int. J. Chem. Kin. 1, 459 (1969).Google Scholar
[11] Bent, B. E., Nuzzo, R. G. and Dubois, L. H., J. Vac. Sci. Technol. A6, 1920 (1988).Google Scholar
[12] Bent, B. E., Zegarski, B. R., Nuzzo, R. G. and Dubois, L. H., in preparation.Google Scholar
[13] Redhead, P. A., Vacuum 12, 203 (1962).Google Scholar
[14] At surface temperatures above 600K, carbon is incorporated into the growing aluminum film [7].Google Scholar
[15] This value was approximated from the exposure necessary to achieve saturation coverage in the TIBA thermal desorption experiments. It is roughly consistent with the van der Waals radius of TIBA [7].Google Scholar