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Why the Photoconductivity Decreases in a-SiC:H and a-SiGe:H when the Amount of Alloying Increases

Published online by Cambridge University Press:  26 February 2011

A. H. Mahan ,
P. Raboisson ,
P. Menna  and
R. Tsut
A. H. Mahan
Affiliation:
Solar Energy Research Institute, Golden, Colorado 80401
P. Raboisson
Affiliation:
Centre National de la Recherche Scientifique, Sophia Antipolis, F-6500 Valbonne, France
P. Menna
Affiliation:
ENEA/FARE-FOTO, C.P. 83, 80055 Portici, Italy
R. Tsut
Affiliation:
Electrical Engineering Dept., North Carolina A&T State Univ., Greensboro, N.C. 27411
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Abstract

Infrared, photoconductivity, and photothermal deflection spectroscopy measurements have been used to probe the relationship between material quality and the amount of microstructure in glow discharge deposited a-SiC:H and a-SiGe:T films. We find that the microstructure is directly responsible for the decrease in photoconductivity observed in both alloys as a function of increased alloy content. The microstructure does this by causing a decrease in steepness of the Urbach tail, thus allowing for an increase in both carrier trapping at the wider band edges and carrier recombination at or near the band tails.

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Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 95: Symposium E – Amorphous Silicon Semiconductors--Pure and Hydrogenated , 1987 , 361
Copyright
Copyright © Materials Research Society 1987

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References

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