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Hole Drift-Mobility Measurements in Contemporary Amorphous Silicon

Published online by Cambridge University Press:  01 February 2011

S. Dinca ,
G. Ganguly ,
Z. Lu ,
E. A. Schiff ,
V. Vlahos ,
C. R. Wronski  and
Q. Yuan
S. Dinca
Affiliation:
Department of Physics, Syracuse University, Syracuse, NY 13244-1130
G. Ganguly
Affiliation:
Department of Physics, Syracuse University, Syracuse, NY 13244-1130
Z. Lu
Affiliation:
BP Solar, Inc., Toano, Virgina 23168
E. A. Schiff
Affiliation:
Department of Physics, Syracuse University, Syracuse, NY 13244-1130
V. Vlahos
Affiliation:
BP Solar, Inc., Toano, Virgina 23168
C. R. Wronski
Affiliation:
BP Solar, Inc., Toano, Virgina 23168
Q. Yuan
Affiliation:
Department of Physics, Syracuse University, Syracuse, NY 13244-1130 Department of Electrical Engineering, Pennsylvania State University, University Park, Pennsylvania 18702
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Abstract

We present hole drift-mobility measurements on hydrogenated amorphous silicon from several laboratories. These temperature-dependent measurements show significant variations of the hole mobility for the differing samples. Under standard conditions (displacement/field ratio of 2×10-9 cm2/V), hole mobilities reach values as large as 0.01 cm2/Vs at room-temperature; these values are improved about tenfold over drift-mobilities of materials made a decade or so ago. The improvement is due partly to narrowing of the exponential bandtail of the valence band, but there is presently little other insight into how deposition procedures affect the hole drift-mobility.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 762: Symposium A – Amorphous and Nanocrystalline Silicon-Based Films – 2003 , 2003 , A7.1
Copyright
Copyright © Materials Research Society 2003

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References

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