Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-24T21:01:04.225Z Has data issue: false hasContentIssue false

Electrical Transport in Mesoporous Silicon Layers

Published online by Cambridge University Press:  28 February 2011

M. Ben-Chorin
Affiliation:
Physics Department E16, Technical University of Munich, D-85747 Garching, Germany
S. Grebner
Affiliation:
Physics Department E16, Technical University of Munich, D-85747 Garching, Germany
F. Wang
Affiliation:
Physics Department E16, Technical University of Munich, D-85747 Garching, Germany
R. Schwarz
Affiliation:
Physics Department E16, Technical University of Munich, D-85747 Garching, Germany
A. Nikolov
Affiliation:
Physics Department E16, Technical University of Munich, D-85747 Garching, Germany
F. Koch
Affiliation:
Physics Department E16, Technical University of Munich, D-85747 Garching, Germany
Get access

Abstract

In order to clarify the role of the enlarged surface area of porous silicon on the electrical conductivity, we have studied the transport in mesoporous silicon layers, for which quantum confinement effects are negligible. We prepare free standing mesoporous films, from highly doped p-type Si wafers. The dark conductivity of the mesoporous layers is activated with an energy of 0.5 eV. Thermopower measurements show negative sign indicating electron conduction. The exposure of these layers to methanol vapor results in an increased conductivity and change of the thermopower magnitude. Photoconductivity measurements and the Steady-State Photocarrier Grating technique (SSPG) are used to evaluate the density of the surface states and the dynamics of the photo-excited carriers. All these results indicate that a large density of surface states exist, which results in a depletion of the free holes.

Type
Research Article
Copyright
Copyright © Materials Research Society 1995

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 Canham, L. T., Appl. Phys. Lett. 57, 1046 (1990).Google Scholar
2 Ben-Chorin, M., Möller, F., Koch, F., Schirmacher, W., Eberhard, M., Phys. Rev. B, in press (1994).Google Scholar
3 Goudeau, P., Naudon, A., Bomchil, G., Herino, R., J. Appl. Phys. 66, 625 (1989).Google Scholar
4 Ben-Chorin, M., Kux, A., Schechter, I., Appl. Phys. Lett. 64,481 (1994)Google Scholar
5 Schwarz, R., Wang, F., Ben-Chorin, M., Grebner, S., Nikolov, A., Koch, F., Thin Solid Films, in press (1994).Google Scholar
6 Ritter, D., Zeldov, E., Weiser, K., Phys. Rev. B 38, 8296 (1988).Google Scholar
7 Madan, A., Shaw, M. P., The Physics and Application of Amorphous Semiconductors (Academic Press, London, 1987) p. 87.Google Scholar
8 Many, A., Goldstein, Y., Grover, N. B., Semicondutcor Surfaces (North Holland, Amsterdam, 1971).Google Scholar
9 Jäntsch, O., Surface Science 3, 155 (1965).Google Scholar
10 Tanielian, M., Phil. Mag. B 45, 435 (1982).Google Scholar
11 Chazalviel, J. N., Winter School on Porous Silicon, Les Houches (1994).Google Scholar