Hostname: page-component-78c5997874-lj6df Total loading time: 0 Render date: 2024-11-17T18:19:25.027Z Has data issue: false hasContentIssue false

Photodegradation in a-Si:H Prepared by Hot-Wire CVD as a Function of Substrate and Filament Temperatures

Published online by Cambridge University Press:  17 March 2011

Daxing Han
Affiliation:
Dept of Phys & Astronomy, Univ of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3255, USA
Guozhen Yue
Affiliation:
Dept of Phys & Astronomy, Univ of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3255, USA
Jing Lin
Affiliation:
Dept of Phys & Astronomy, Univ of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3255, USA
Hitoe Habuchi
Affiliation:
Gifu National College of Technology, Sinsei-cho, Motosu-gun, Gifu, 501-04, Japan
Eugene Iwaniczko
Affiliation:
National Renewable Energy Laboratory, Golden, CO 80401, USA
Qi Wang
Affiliation:
National Renewable Energy Laboratory, Golden, CO 80401, USA
Get access

Abstract

We have studied light-soaking effects, such as photoconductivity (PC) degradation kinetics, the changes of conductivity activation energy, Ea, and the defect density of states (DOS) in a-Si:H films deposited by hot-wire CVD. Films were deposited in a substrate temperature range from 280 to 440 °C for filament temperatures of 1900 and 2100 °C. We find that (a) the photodegradation kinetics does not follow the stretched exponential rule for all of the samples; (b) the Fermi level position moves up after light-soaking for most samples; and (c) the metastable defect DOS deduced from sub-band gap absorption is not consistent with that deduced from the electron mobility-lifetime product. The results are discussed according to the possible mechanism in which charged defects exist in hot-wire a-Si:H films.a

Type
Research Article
Copyright
Copyright © Materials Research Society 2000

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. Staebler, D.L. and Wronski, C.R., Appl. Phys. Lett. 31, 292 (1977).Google Scholar
2. Fritzsche, H., Mat. Res. Soc. Symp. Proc. 467, 19 (1997).Google Scholar
3. Stutzmann, M., Jakson, W. B., and Tsai, C. C., Phys. Rev. B32, 23 (1985).Google Scholar
4. Branz, H. M., Asher, Sally, Gleskova, H. and Wagner, S., Phys. Rev. B59, 5513 (1999).Google Scholar
5. Mahan, A. H., Carapella, J., Nelson, B. P., Crandall, R. S., and Balberg, I., J. Appl. Phys. 69, 6728 (1991).Google Scholar
6. Wu, Y., Stephen, J. T., Han, Daxing, Rutland, J. M., Crandall, R.S., and Mahan, A. H., Phys. Rev. Lett. 77, 2049 (1996).Google Scholar
7. Liu, Xiao, White, B. E. Jr, and Pohl, R. O., Iwanizcko, E., Jones, K. M., Mahan, A. H., Nelson, B. N., Crandall, R. S., and Veprek, S., Phys. Rev. Lett., 78, 4418 (1997).Google Scholar
8. Williamson, D.L., Mat. Res. Soc. Symp. Proc. 557, 251 (1999).Google Scholar
9. Han, Daxing and Fritzsche, H., J. Non-Cryst. Sol. 59/60, 397 (1983).Google Scholar
10. Jackson, W.B. and Amer, N.M., Phys. Rev. B 25, 5559 (1982).Google Scholar
11. Branz, H. M. and Silver, M., Phys. Rev. B 42, 7420 (1990).Google Scholar
12. Han, Daxing, Baugh, Jonathan, Yue, Guozhen, and Wang, Qi, unpublished.Google Scholar