Hostname: page-component-77c89778f8-rkxrd Total loading time: 0 Render date: 2024-07-24T18:09:45.164Z Has data issue: false hasContentIssue false

Evolution of D0 and non-D0 Light Induced Defect States in a-Si:H Materials and Their Respective Contribution to Carrier Recombination

Published online by Cambridge University Press:  21 March 2011

J. M. Pearce
Affiliation:
Center for Thin Film Devices The Pennsylvania State University
J. Deng
Affiliation:
Center for Thin Film Devices The Pennsylvania State University
V. Vlahos
Affiliation:
Center for Thin Film Devices The Pennsylvania State University
R. W. Collins
Affiliation:
Center for Thin Film Devices The Pennsylvania State University
C. R. Wronski
Affiliation:
Center for Thin Film Devices The Pennsylvania State University
J. Whitaker
Affiliation:
University of Utah
P. C. Taylor
Affiliation:
University of Utah
Get access

Abstract

A study has been carried out on the evolution of light induced defects in protocrystalline (diluted) a-Si:H films under 1 sun illumination. A room temperature reversal is observed in the photocurrents at 25°C, which is consistent with the relaxation in the recombination currents on corresponding p-i-n solar cells. It is also consistent with the pressure of “fast” states such as have been observed after high intensity illumination. Even with the limitations imposed by the relaxation in the light induced changes on the subgap absorption measurements, the evolution of distinctly different gap states centered around 0.9 and 1.15eV from the conduction band was identified. The kinetics of the electron occupied states, kN(E), at these two energies is compared with that of the neutral dangling bond (D0) densities as measured with electron spin resonance. Because of the similarity between the preliminary results of these kinetics it has not been possible to identify which states correspond to the D0 nor to draw any reliable conclusions about the nature of the different states.

Type
Research Article
Copyright
Copyright © Materials Research Society 2004

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. Schumm, G., Lotter, E., and Bauer, G.H., Appl. Phys. Lett. 60, p. 3262 (1992).Google Scholar
2. Ganguly, G., Yamasaki, S., and Matsuda, A., Phil. Mag. B 63(1) p. 281 (1991).Google Scholar
3. Gunes, M. and Wronski, C.R., J. Appl. Phys. 81, p. 3526 (1997).Google Scholar
4. Pearce, J., Niu, X., Koval, R., Ganguly, G., Carlson, D., Collins, R.W., Wronski, C.R., Mat. Res. Soc. Proc., 664, A12.3 (2001).Google Scholar
5. Han, D. and Fritzsche, H., J. Non-Cryst. Solids, 59–60, p. 397 (1983).Google Scholar
6. Stradins, P. and Fritzsche, H., Philos Mag. B 69, p.121 (1994).Google Scholar
7. Yang, L., Chen, L., and Catalano, A., Appl. Phys. Lett. 59, p. 840 (1991).Google Scholar
8. Xu, X., Yang, J., and Guha, S., Mat. Res. Soc. Proc., 297 649 (1993).Google Scholar
9. Pearce, J. M., Koval, R. J., Niu, X., May, S. J., Collins, R.W., and Wronski, C. R., 17th European Photovoltaic Solar Energy Conference Proceedings, 3, pp. 28422845 (2002).Google Scholar
10. Pearce, J. M., Deng, J., Collins, R. W., and Wronski, C. R., Appl. Phys. Lett., 83(18), pp. 37253727 (2003).Google Scholar
11. Pearce, J. M., Deng, J., Vlahos, V., Collins, R. W., and Wronski, C. R., “Light Induced Changes in Two Distinct Defect States At and Below Midgap in a-Si:H”, Proceedings of the 3rd World Conference on Photovoltaic Energy, 5O–D14 (2003).Google Scholar
12. Jiao, L., Liu, H., Semoushikina, S., Lee, Y., Wronski, C. R., Appl. Phys. Lett. 69, p.3713 (1996).Google Scholar
13. Deng, J., Pearce, J.M., Vlahos, V., Collins, R.W., and Wronski, C.R., “Characterization of the Bulk Recombination in Hydrogenated Amorphous Silicon Solar Cells”, This conference (2004).Google Scholar
14. Wronski, C. R., Collins, R. W., Vlahos, V., Pearce, J. M., Deng, J., Albert, M., Ferreira, G. M., and Chen, C., “Optimization of Phase-Engineered a-Si:H-Based Multijunction Solar Cells”, National Renewable Energy Laboratory Annual Report, Contract #: NDJ-2-30630-01, (2004).Google Scholar
15. Wiedeman, S., Bennett, M. S., and Newton, J. L., Mater. Res. Soc. Symp. Proc. 95, pp. 145150 (1987).Google Scholar
16. Yan, B. and Taylor, P. C., Mat. Res. Soc. Symp. Proc. 507, 805 (1998).Google Scholar
17. Taylor, P.C. and Ohlsen, W. D., Solar Cells, 9 pp. 113118 (1983).Google Scholar