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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.

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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