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Microstructural and Electronic Properties of Hydrogenated Amorphous Silicon Films Deposited by Magnetron Reactive Sputtering.

Published online by Cambridge University Press:  26 February 2011

Mustafa Pinarbasi ,
Nagi Maley ,
Alan Myers ,
Igor Szafranek ,
John R. Abelson  and
John A. Thornton
Mustafa Pinarbasi
Affiliation:
Department of Materials Science and Engineering, the Coordinated Science Laboratory, and the Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801.
Nagi Maley
Affiliation:
Department of Materials Science and Engineering, the Coordinated Science Laboratory, and the Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801.
Alan Myers
Affiliation:
Department of Materials Science and Engineering, the Coordinated Science Laboratory, and the Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801.
Igor Szafranek
Affiliation:
Department of Materials Science and Engineering, the Coordinated Science Laboratory, and the Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801.
John R. Abelson
Affiliation:
Department of Materials Science and Engineering, the Coordinated Science Laboratory, and the Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801.
John A. Thornton
Affiliation:
”In memory of John A. Thornton”
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Abstract

Hydrogenated amorphous silicon (a-Si:H) films have been deposited by dc magnetron reactive sputtering in an Ar+H2 working gas. In this process, the hydrogen content A controlled by two independent variables: the substrate temperature and the hydrogen partial pressure in the deposition chamber. For a wide range of deposition conditions studied, it is shown that total hydrogen content of the films, as inferred from IR absorption, is uniquely related to the hydrogen bonding and the microstructure. We report films of high electronic quality, deposited between 200–300 °C, in which hydrogen bonding varies from predominantly SiH to mixed SiH and SiH2 modes as the hydrogen content is increased. This struciral change is reflected in hydrogen evolution spectra. In addition to peaks at ˜500 and ˜600 ° C, a low-temperature peak (350–400 C) has been observed for the films which have high hydrogen content and consequently are rich in SiH2. The low temperature peak is absent in SiH dominant films. However, the low-temperature peak is not associated with a columnar morphology because SEM images of fracture cross-sections are featureless for SiH dominant films and have a “bumpy” texture for high SiH2 content films. We propose that in our SiH2 rich films, excess hydrogen leads to a void rich but non-columnar morphology. Preliminary measurements of the Staebler-Wronski effect using AM-1 light show a low susceptibilty to degradation in both types of films. The different electronic properties of the films indicate that the quality of magnetron sputtered films does not necessarily correlate with the IR absorption peaks in a simple manner.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 118: Symposium E – Amorphous Silicon Technology , 1988 , 537
Copyright
Copyright © Materials Research Society 1988

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References

1) Pinarbasi, M., Chou, L. S., Maley, N., Myers, A., Leet, D., and Thornton, J. A., Superlattices and Microstructures Vol.3, No.4,331 (1987).Google Scholar
2) Moustakas, T.D., in Hydrogenated Amorphous Silicon, Semiconductors and Semimetals, Vol.21–A, edited by J., Pankove, Academic Press, New-York(1984) p. 55.Google Scholar
3) Rubel, H., Schroder, B., and Geiger, J., Journal of Vacuum Science and Technology A 4,1855 (1986).Google Scholar
4) Rocheleau, , Hegedus, S.S., Buchanan, W., and Tullman, R., paper presented at 19th IEEE Photovoltaic Specialists Coference, New Orleans, LA, May 4–8, 1987.Google Scholar
5) Brodsky, M. H., Cardona, M., Cuomo, J.J., Physical Review B 16, 3556 (1977).Google Scholar
6) Freeman, E.C. and Paul, W., Physical Review B 18,4288 (1978)Google Scholar
7) Knights, J.C., Lucovsky, G. and Nemanich, R.J., Journal of Non-Crystalline Solids 32,393 (1979)CrossRefGoogle Scholar
8) Beyer, W. and Wagner, H., Journal of Non-Crystalline Solids, 59&60, 161 (1983).Google Scholar
9) Gert, Ehrlich, private communication.Google Scholar
10) Biegelsen, D.K., Street, R.A., Tsai, C.C., and Knights, J.C., Physical Review B, Vol.20, No.12, 4839 (1979).Google Scholar
11) Baum, J., Gleason, K.K., Pines, A., Garroway, A.N., and Reimer, J.A., Physical Review Letters, Vol.56,No.13,1377 (1986).Google Scholar
12) Rose, A., Concepts in Phoconductivity and Allied Problems, Interscience, New York (1963).Google Scholar
13) Wronski, C.R., Abeles, B., Tiedje, T. and Cody, G.D., Solid State Communications, Vol.44,No.10,1423–1426(1982)Google Scholar
14) Staebler, D.L., Wronski, C.R., Applied Physics Letters,31,292(1977)Google Scholar
15) Stutzman, M., Jackson, W.B., Tsai, C.C., Physical Review, B 32,23(1985).CrossRefGoogle Scholar