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Factors Influencing the Quality of a-Si:H Films Deposited by the “HOT WIRE” Technique

Published online by Cambridge University Press:  16 February 2011

Edith C. Molenbroek ,
A. H. Mahan ,
E. J. Johnson  and
A. C. Gallagher
Edith C. Molenbroek
Affiliation:
National Renewable Energy Laboratory, Golden, Co 80401
A. H. Mahan
Affiliation:
National Renewable Energy Laboratory, Golden, Co 80401
E. J. Johnson
Affiliation:
National Renewable Energy Laboratory, Golden, Co 80401
A. C. Gallagher
Affiliation:
Joint Institute for Laboratory Astrophysics, University of Colorado and National Institute of Standards and Technology, Boulder, CO 80309–0440
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Abstract

Device quality a-Si:H has been deposited at 3 Å/s using the “hot wire” technique with 1% SiH4 in He as a source gas. To achieve this deposition rate despite the high dilution, the filament was positioned at 1–2 cm from the substrate. This short distance introduces a large non-uniformity across the substrate in the deposition rate as well as in the film properties. This experimental fact was used to analyze which factors in the deposition determine film quality. We find that radiation from the filament is not an important factor. Data taken from samples deposited at various distances, pressures and flows suggest that the film quality is influenced by radical reactions with SiH4. However, this assumption alone predicts too strong a pressure dependence. The influence of deposition rate as an additional factor can explain the results.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 336: Symposium A – Amorphous Silicon Technology - 1994 , 1994 , 43
Copyright
Copyright © Materials Research Society 1994

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References

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