Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-26T04:38:07.439Z Has data issue: false hasContentIssue false
  • English
  • Français

Oxygen Effects in Mechanically Alloyed Si80 Ge20 Doped with GaP and P

Published online by Cambridge University Press:  15 February 2011

B. A. Cook ,
J. L. Harringa  and
B. J. Beaudry
B. A. Cook
Affiliation:
Ames Laboratory, Iowa State University, Ames, IA 50010
J. L. Harringa
Affiliation:
Ames Laboratory, Iowa State University, Ames, IA 50010
B. J. Beaudry
Affiliation:
Ames Laboratory, Iowa State University, Ames, IA 50010
Get access

Abstract

A neutron activation study was performed to follow the total oxygen content during the preparation sequence of mechanically alloyed Si-20 at.% Ge n-type alloys using both elemental powders and chunk starting materials. The Si-20 at. % Ge alloys were doped with 1.6 at. % GaP and 3.4.at. % P and the total oxygen concentration was measured in the starting materials, after six hours of mechanical alloying in a helium environment, after hot pressing, and after a short 1100°C soak in fused silica ampoules. The alloys containing high oxygen levels showed low carrier mobility and low thermal conductivity whereas those containing low oxygen showed high mobility and thermal conductivity. The microstructure, as observed by optical metallography and SEM, was found to differ greatly with oxygen content as the low oxygen alloys showed relatively large, well defined grains and the high oxygen alloys showed evidence of poor sintering and limited grain growth.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 234: Symposium V – Modern Perspectives on Thermoelectrics and Related Materials , 1991 , 111
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. Bhandari, C. M. and Rowe, D. M., Contemp. Phys. 21, 219 (1980).Google Scholar
2. Vining, C. B., Laskow, W., Hanson, J. O., Beck, R. R. Van der, and Gorsch, P. D., to be published J. Appl. Phys.Google Scholar
3. Owusu-Sekyere, K., Jesser, W. A., and Rosi, F. D., Mater. Sci. Eng. B3, 231 (1989).CrossRefGoogle Scholar
4. Needels, N., Joannopoulos, J. D., Bar-Yam, Y., and Pantelides, S. T., Phys. Rev. B 43, 4208 (1991).Google Scholar
5. Doremus, R.H., J. Appl. Phys. 66, 4441 (1989).CrossRefGoogle Scholar
6. Cook, B. A., Beaudry, B. J., Harringa, J. L., and Barnett, W. J. in Proceedings of the Ninth International Conference on Thermoelectrics, edited by Vining, C. B. (Jet Propulsion Laboratory, Pasadena, CA, 1990), p. 234.Google Scholar
7. Cook, B. A., Beaudry, B. J., Harringa, J. L., and Barnett, W. J. in Proceedings of the Eighth Symposium on Space Nuclear Power Systems, edited by El-Genk, M. S. and Hoover, M. D. (American Institute of Physics, New York, 1991), p. 431.Google Scholar
8. Benjamin, J. S., Sci. American 5, 40 (1976).Google Scholar
9. Davis, R. M. and Koch, C. C., Scripta Met. 21, 305 (1987).Google Scholar
10. Sundaresan, R. and Froes, F. H., J. Meals 8, 22 (1987).Google Scholar
11. Froes, F. H., J. Metals 41, 25 (1989).Google Scholar
12. Amano, T., Beaudry, B. J., Gschneidner, K. A. Jr., Hartman, R., Vining, C. B., and Alexander, C. A., J. Appl. Phys. 62, 819 (1987).Google Scholar
13. Chasmar, R. P. and Stratton, R., J. Electron. Control 7, 52 (1959).CrossRefGoogle Scholar
14. Fluerial, J. and Borshchevsky, B. in Proceedings of the Ninth International Conference on Thermoelectrics, edited by Vining, C. B. (Jet Propulsion Laboratory, Pasadena, CA, 1990), p. 206.Google Scholar