Hostname: page-component-848d4c4894-m9kch Total loading time: 0 Render date: 2024-06-02T06:03:31.426Z Has data issue: false hasContentIssue false

GaAs(100) Surface Modifications at Elevated Temperatures, Studied By In-Situ Spectroscopic Ellipsometry

Published online by Cambridge University Press:  25 February 2011

Huade Yao
Affiliation:
University of Nebraska, Center for Microelectronic and Optical Materials Research, and Department of Electrical Engineering, Lincoln, NE 68588–0511
Paul G Snyder
Affiliation:
University of Nebraska, Center for Microelectronic and Optical Materials Research, and Department of Electrical Engineering, Lincoln, NE 68588–0511
John A Woollam
Affiliation:
University of Nebraska, Center for Microelectronic and Optical Materials Research, and Department of Electrical Engineering, Lincoln, NE 68588–0511
Get access

Abstract

Spectroscopic ellipsometric (SE) measurements of GaAs (100) were carried out in an ultrahigh vacuum (UHV) chamber, without arsenic overpressure, at temperatures ranging from room temperature (RT) to ∼610°C. Surface changes induced at elevated temperatures were monitored by in-situ spectroscopic ellipsometry. The SE data clearly displayed in real time the process of desorption of the GaAs-surface-oxide overlayer at ∼580°C. In addition, changes in the near-surface region were observed before and after the oxide desorption. The near-subsurface region (top 50–100 Å) became less optically dense after being heated to 540°C or higher. For comparison, a pre-arsenic-capped molecular-beam-epitaxy (MBE)-grown GaAs surface was also studied. After the arsenic cap was evaporated off at ∼350°C, this surface remained smooth and clean as it was heated to higher temperatures.

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. Azzam, R.M.A. and Bashara, N.M., Ellipsometry and Polarized Light, (North-Holland, Amsterdam, 1977).Google Scholar
2. Aspnes, D.E., in Handbook of Optical Constants of Solids ed. Palik, E.D., (Academic Press, New York, 1985) p89.Google Scholar
3. Yao, H.D., Snyder, P.G., and Woollam, J.A., (to be published).Google Scholar
4. Aspnes, D.E. and Studna, A.A., Phys. Rev. B 27, 985 (1983).Google Scholar
5. Yao, H.D., Snyder, P.G. and Woollam, J.A., Proceedings of ICEM-2 (in press).Google Scholar
6. Snyder, P.G., Rost, M.C., Bu-Abbud, G.H., Woollam, J.A. and Alterovitz, S.A., J. Appl. Phys. 60, 3293 (1986).Google Scholar
7. Studna, A.A., Aspnes, D.E., Florez, L.T., Wilkens, B.J., Harbison, J.P., and Ryan, R.E., J. Vac. Sci. Technol. A7, 3291 (1989).Google Scholar
8. Aspnes, D.E. and Studna, A.A., Appl. Phys. Lett. 39, 316 (1981).Google Scholar
9. Aspnes, D.E. and Theeten, J.B., Phys. Rev. B 20, 3292 (1979).Google Scholar
10. Foxon, C.T., Harvey, J.A. and Joyce, B.A., J. Phys. Chem. Solids 34, 1693 (1973).Google Scholar
11. Aspnes, D.E., in Handbook of Optical Constants of Solids ed. Palik, E.D., (Academic Press, New York, 1985) p 89.Google Scholar
12. Aspnes, D.E., Quinn, W.E., and Gregory, S., Appl. Phys. Lett. 56, 2569 (1990).Google Scholar
13. Aspnes, D.E., Schwartz, G.P., Gualtieri, G.J., Studna, A.A., and Schwartz, B., J. Electrochem. Soc. 128, 590 (1981).Google Scholar