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Doping, compensation, and photosensitivity of detector grade CdTe

Published online by Cambridge University Press:  31 January 2011

V. Babentsov
Affiliation:
Institute for Semiconductor Physics, Kiev 03028, Ukraine
J. Franc*
Affiliation:
Charles University, Faculty of Mathematics and Physics, Institute of Physics, Prague CZ 121 16, Czech Republic
A. Fauler
Affiliation:
Materialforschungszentrum, Freiburg D-79104, Germany
M. Fiederle
Affiliation:
Materialforschungszentrum, Freiburg D-79104, Germany
R.B. James
Affiliation:
Nonproliferation and National Security Directorate, Brookhaven National Laboratory, Upton, New York 11973
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

We studied the resistivity, photosensitivity, photoluminescence, and surface photovoltage of CdTe crystals doped with Ge or Sn to extend our knowledge of the influence of the deep-donor level on compensation and afterglow effects. We demonstrated a strong correlation between photosensitivity caused by photoelectrons with Fermi-level variations near the GeCd0/2+ or SnCd0/2+ energy levels. Surface photovoltage measurements confirmed that when the concentration of residual acceptors varied along the direction of growth, then trapping conditions dramatically changed as a defect was converted from a neutral state to doubly charged positive one.

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Articles
Copyright
Copyright © Materials Research Society 2008

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References

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