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The Development of Infrared Photosensitive Material Based on Polycrystalline PbS Films

Published online by Cambridge University Press:  10 February 2011

C. Abarbanel ,
R. Shneck ,
Z. Dashevsky  and
S. Rotman
C. Abarbanel
Affiliation:
Department of Electrical Engineering, Ben-Gurion University of the Negev, P.O.B. 653, Beer-Sheva 84105, Israel
R. Shneck
Affiliation:
Department of Electrical Engineering, Ben-Gurion University of the Negev, P.O.B. 653, Beer-Sheva 84105, Israel
Z. Dashevsky
Affiliation:
Department of Electrical Engineering, Ben-Gurion University of the Negev, P.O.B. 653, Beer-Sheva 84105, Israel E-mail: zdashev@bgumail.bgu.ac.il
S. Rotman
Affiliation:
Ben-Gurion University of the Negev, P.O.B. 653, Beer-Sheva 84105, Israel
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Abstract

Polycrystalline thin films of lead sulphide were deposited on glass substrates by the hot wall technique. The grain size varied from 100 to 500 A by varying the growth rate and the substrate temperature. The grain boundaries are assumed to influence the optoelectronic properties of polycrystalline films by generating potential energy relieves, estimated to reach 0.1 eV. We investigated the influence of the barrier height by introducing impurity atmospheres into the grain boundaries. Oxygen and indium were introduced into the films by diffusion from a gas phase. Conductivity was measured in the 80-300 K range. It rises with increasing temperature in oxygen doped films, indicating that conductivity is a thermal activation process. In the same time the conductivity of In doped PbS films decreases with temperature like in PbS single crystals. Photoconductivity was observed in films annealed in oxygen, which was significant up to room temperature. Carrier lifetime was found to decrease with rising temperature and be larger in films annealed in oxygen.

A model is proposed to explain the optoelectronic behavior of the polycrystalline films. It is proposed that charge accumulation near grain boundaries set up potential barriers for free carriers. The barriers increase by oxygen and decreases by indium doping. The charge carriers generated by an illumination become spatially separated at grain boundaries. This separation retards their recombination and increases their lifetime, giving rise to persistent photoconductivity and potential high photosensitivity.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 607: Symposium OO – Infrared Applications of Semiconductors III , 1999 , 353
Copyright
Copyright © Materials Research Society 2000

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References

1. Kruse, P.W., McGlauchlin, L.D., McQusistan, R.B.. Elements of infrared technology. John Willey. New-York, 1962, pp. 344–436.Google Scholar
2. Neustroev, L.N. and Osipov, V.V., Fiz. Tekh. Popuprovodn. 20, 59 (1986) [Sov. Phys. Semicond., 20, 34 (1986)].Google Scholar
3. Lyahovitskaya, V., Kaplan, L., Goswami, J. and Cahen, D., Proceedings of the 12-th International Conference on Crystal Growth, Israel, p. 302 (1998).Google Scholar
4. Gaskov, A.M., Goddenvezer, A.A., Sokolov, I.A., Zlomanov, V.P., Dokl Akad. Nauk SSSR 269, 607 (1983). [Sov. Phys. Sokl. 28, 212 (1983)].Google Scholar
5. Kaidanov, V.I., Ravich, Yu. I., Soviet Physics Uspekhi 28, p. 31 (1985).Google Scholar
6. Dashevsky, Z.M. and Rulenko, M.P., Fiz. Tekh. Popuprovodn. 27, 662 (1993) [Sov. Phys. Semicond., 27, 366 (1993)].Google Scholar
7. Fish, G., Bouevitch, O., Rev. Sci. Instrument, 64, 2947 (1993).Google Scholar