Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-18T08:47:54.782Z Has data issue: false hasContentIssue false
  • English
  • Français

Femtosecond Far-Infrared Studies of Carrier Dynamics in Hydrogenated Amorphous Silicon and Silicon-Germanium Alloys

Published online by Cambridge University Press:  01 February 2011

A. V. V. Nampoothiri ,
B. P. Nelson  and
S. L. Dexheimer
A. V. V. Nampoothiri
Affiliation:
Department of Physics, Washington State University, Pullman, WA
B. P. Nelson
Affiliation:
National Renewable Energy Laboratory, Golden, CO
S. L. Dexheimer
Affiliation:
Department of Physics, Washington State University, Pullman, WA
Get access

Abstract

We present femtosecond time-resolved studies of the photoexcited carrier response in the far-infrared spectral range in PECVD a-Si:H and a-SiGe:H thin films. The experiments are carried out using an optical pump / terahertz (THz) probe technique, in which a femtosecond pump pulse excites carriers in the sample and a time-delayed probe pulse measures the resulting change in the far-infrared optical properties as a function of time delay following the excitation. These measurements are sensitive to carrier processes at low energy, corresponding to a range of approximately 1 - 10 meV, a key energy scale in these materials. We find that the observed photoexcited carrier dynamics are consistent with trapping of carriers into band tail states on a picosecond time scale.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 762: Symposium A – Amorphous and Nanocrystalline Silicon-Based Films – 2003 , 2003 , A4.4
Copyright
Copyright © Materials Research Society 2003

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

1. Fauchet, P. M., Hulin, D., Vanderhaghen, R., Mourchid, A. and Nighan, J. W. L., J. Non-Cryst. Solids 141, 76 (1992), and references therein.Google Scholar
2. Esser, A., Heesel, H., Kurz, H., Wang, C., Parsons, G. N. and Lucovsky, G., J. Appl. Phys. 73, 1235 (1993).Google Scholar
3. Shkrob, I. A. and Crowell, R. A., Phys. Rev. B 57, 12207 (1998).Google Scholar
4. Dexheimer, S. L., Zhang, C. P., Liu, J., Young, J. E. and Nelson, B. P., Materials Research Society Proc. v.715, A2.1 (2002).Google Scholar
5. Zhang, X.-C., J. Lumin. 66-67, 488 (1996).Google Scholar
6. Beard, M. C., Turner, G. M., and Schmuttenmaer, C. A., Phys.Rev.B 62, 15764 (2000).Google Scholar
7. Beard, M. C., Turner, G. M., and Schmuttenmaer, C. A., J. Appl. Phys. 90, 5915 (2000).Google Scholar
8. Scher, H. and Montroll, E. W., Phys. Rev. B 12, 2455 (1975).Google Scholar
9. Nampoothiri, A.V.V. and Dexheimer, S.L., to be published.Google Scholar