Hostname: page-component-7bb8b95d7b-cx56b Total loading time: 0 Render date: 2024-09-26T03:15:54.105Z Has data issue: false hasContentIssue false

Midgap Defects in a-SiGe:H Devices from Capacitance Measurements

Published online by Cambridge University Press:  25 February 2011

Steven S. Hegedus
Affiliation:
Institute of Energy Conversion University of Delaware Newark, Delaware 19716
Theodore X. Zhou
Affiliation:
Institute of Energy Conversion University of Delaware Newark, Delaware 19716
Get access

Abstract

We have measured the capacitance of a-SiGe:H p-i-n solar cells as functions of temperature, frequency and bias. The density of states at the Fermi level g(EF) has been determined from two methods. We find that g(EF) increases from 1–2×1016 to 5–10×1017/(cm3eV) as the Ge content increases from 0 to 63%.

Type
Research Article
Copyright
Copyright © Materials Research Society 1989

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. Mackenzie, K., Burnett, J., Eggert, J., Li, Y., Paul, W., Phys. Rev. B 38, 6120,(1988).Google Scholar
2. Aljishi, S., Smith, Z., Wagner, S., in Advances in Amorphous Semiconductors, edited by Fritzsche, H., (World Scientific Publishing, Singapore, 1988), p. 887.Google Scholar
3. Matsuura, H., J. Appl. Phys. 64, 1964,(1988).Google Scholar
4. Rocheleau, R., Hegedus, S., Buchanan, W., Jackson, S., Appl. Phys. Lett. 51, 133,(1987).CrossRefGoogle Scholar
5. Hegedus, S., Rocheleau, R., Tullman, R., Albright, D., Saxena, N., Buchanan, W., Schubert, K., Dozier, R., Proc. 20th IEEE Photovoltaic Spec. Conf. (IEEE, NY,NY,1989 in press).Google Scholar
6. Michelson, C., Gelatos, A., Cohen, J., Appl. Phys. Lett. 47, 412,(1985).Google Scholar
7. Cohen, J.D., Lang, D., Phys. Rev. B25, 5321,(1982).Google Scholar
8. Jousse, D., Deleonibus, S., J. Appl. Phys. 54, 4001,(1983).Google Scholar
9. Cohen, J.D., in Semiconductors and Semimetals-Vol. 21C, edited by Pankove, J. (Academic Press, Orlando, FL, 1984) p. 9.Google Scholar
10. Viktorovitch, P., J. Appl. Phys. 52, 1392,(1981).Google Scholar
11. Beichler, J., Fuhs, W., Mell, H., Welsch, H., J. Non-Cryst. Sol. 35&36,587, (1980).Google Scholar
12. Cohen, J.D., Mahavadi, K., Zellama, K., Harbison, J., Delahoy, A., in Mat. Issues in Amor. Silicon Tech. edited by Adler, D., Hamaka, Y., Madan, A. (MRS Proc. 70, Pittsburgh, PA, 1986), p. 213.Google Scholar
13. Lang, D., Cohen, J.D., Harbison, J., Phys. Rev B 25, 5285, (1982).CrossRefGoogle Scholar
14. We have used value of ε which accounts for variation in Ge composition by assuming εx=12 for a-Si:H and 16 for a-Ge:H, and that ε. scaled linearly with Ge between the endpoints.Google Scholar
15. Hegedus, S., Rocheleau, R., Cebulka, J., Baron, B., J. Appl. Phys. 60, 1046,(1986).Google Scholar
16. Weisfield, R., Ph.D. Dissertation, Harvard Univ.,(1983).Google Scholar
17. Sharma, D., Narasimhan, K., Kumar, S., Arora, B., Paul, W., Turner, W., J. Appl. Phys. 65, 1996,(1989).Google Scholar