Hostname: page-component-7c8c6479df-fqc5m Total loading time: 0 Render date: 2024-03-28T15:48:44.313Z Has data issue: false hasContentIssue false

Ftir Studies Of Organometallic Surface Chemistry Relevant To Atomic Layer Epitaxy.

Published online by Cambridge University Press:  16 February 2011

Ananth V. Annapragada
Affiliation:
Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139.
Sateria Salim
Affiliation:
Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139.
Klavs F. Jensen
Affiliation:
Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139.
Get access

Abstract

The adsorption and surface reactions of trimethylgallium and tertiarybutylarsine on GaAs(100) surfaces have been investigated by Fourier transform infrared spectroscopy. Adsorbed methyl groups resulting from the dissociative chemisorption of trimethylgallium on GaAs(100) are shown to form As-H and CH2 species on the surface. The CH2 groups are stable on the surface at temperatures as high as 550 °C. The surface coverage is low (∼0.2% of a monolayer) and is reduced by the presence of hydrogen on the surface. This dehydrogenation of surface methyl groups could be a possible route to carbon incorporation in GaAs grown by atomic layer epitaxy. Tertiarybutylarsine is shown to decompose primarily by homolysis to form a tertiary butylgroup and AsH2. At temperatures below 400°C on trimethylgallium dosed surfaces, the decomposition products appear to cause the hydrogenation of methylene groups remaining from prior surface dosing with trimethylaallium. At high temperatures, the tertiarybutyl radical appears to undergo dehydrogenation reactions to an unsaturated species which is stable on the surface. In contrast, the dehydrogenation does not appear to occur on surfaces treated with tertiarybutylarsine. The data for trimethylgallium and tertiarybutylarsine support the general assertion that surface As-H species play a critical role in the removal of hydrocarbon species from the growth surface.

Type
Research Article
Copyright
Copyright © Materials Research Society 1991

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Memmert, U. and Yu, M., Appl. Phys. Lett. 56 1883 (1990)CrossRefGoogle Scholar
2. Donnelly, V.M. and MacCaulley, J.A., Surf Sci. 238 34 (1990)CrossRefGoogle Scholar
3. Creighton, J.R.,Surf Sci. 234 287 (1990)CrossRefGoogle Scholar
4. Haacke, G., Watkins, S.P., and Burkhard, H., Appl. Phys. Lett. 54, 2029 (1989).CrossRefGoogle Scholar
5. Maa, B.Y. and Dapkus, P.D., Mat.Res.Soc. Symp.Proc., this symposiumGoogle Scholar
6. Annapragada, A.V. and Jensen, K.F., Mat.Res.Soc. Symp.Proc. 204 53 (1991).CrossRefGoogle Scholar
7. Maslowsky, E. Jr., Vibrational spectra of organometallic compounds, Wiley Interscience (1977)Google Scholar
8. Bellamy, L.J., The Infrared Spectraof Complex Molecules, Chapman and Hall (1980)CrossRefGoogle Scholar
9. Lee, F., Backman, A.L., Lin, R., Gow, T.R., and Masel, R.I., Surf. Sci. 216 173 (1989).CrossRefGoogle Scholar
10. Creighton, J.R., Mat.Res.Soc. Symp. Proc. 131 129 (1989).CrossRefGoogle Scholar
11. Sadwicke, L. P, Wang, K.L., Joseph, D.L., and Hicks, R.F., J.Vac. Sci. Tech. B7 273 (1989).CrossRefGoogle Scholar
12. Mokwa, W., Kohl, D., and Heiland, G., Phys. Rev. B 29(12) 6709 (1984)CrossRefGoogle Scholar
13. Brainard, R.L. and Madix, R., J. Am.Chem.Soc. 111 3826 (1989)CrossRefGoogle Scholar
14. Lum, R.M., Klingert, J.K., and Lamont, M.G., J. Crystal Growth 89, 137 (1988).CrossRefGoogle Scholar