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Title: Study of the impurity photoconductivity in p-InSb using epitaxial p{sup +} contacts

Abstract

The optical absorption coefficient α in p{sup +}-InSb layers (with hole concentrations of p ≈ 1 × 10{sup 17}–1.2 × 10{sup 19} cm{sup –3}), grown by liquid-phase epitaxy on p-InSb substrates, is measured in the spectral range of 5-12 µm at 90 K, and the impurity photoconductivity is measured (at 60 and 90 K) in p{sup +}–p structures. It is found that a in the p{sup +} layers reaches a value of 7000 cm{sup –1} (at p ≈ 2 × 10{sup 19} cm{sup –1}). It is shown that the measured substrate value of (α ≈1–3 cm{sup –1}) is overestimated in comparison with estimates (α ≈ 0.1 cm{sup –1}) based on comparing the photoconductivity data. This discrepancy is explained by the fact that the optical transitions of holes responsible for photoconductivity are obscured by the excitation of electrons to the conduction band. The photoionization cross section for these transitions does not exceed 1 × 10{sup –15} cm{sup 2}.

Authors:
 [1]
  1. National Academy of Sciences of Azerbaijan, Abdullaev Institute of Physics (Azerbaijan)
Publication Date:
OSTI Identifier:
22649731
Resource Type:
Journal Article
Resource Relation:
Journal Name: Semiconductors; Journal Volume: 50; Journal Issue: 8; Other Information: Copyright (c) 2016 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ABSORPTION; COMPARATIVE EVALUATIONS; CONCENTRATION RATIO; CROSS SECTIONS; ELECTRONS; EXCITATION; HOLES; INDIUM ANTIMONIDES; LAYERS; LIQUID PHASE EPITAXY; PHOTOCONDUCTIVITY; PHOTOIONIZATION; P-TYPE CONDUCTORS; SUBSTRATES; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE 0013-0065 K; TEMPERATURE RANGE 0065-0273 K

Citation Formats

Eminov, Sh. O., E-mail: shikhamirem@gmail.com. Study of the impurity photoconductivity in p-InSb using epitaxial p{sup +} contacts. United States: N. p., 2016. Web. doi:10.1134/S1063782616080108.
Eminov, Sh. O., E-mail: shikhamirem@gmail.com. Study of the impurity photoconductivity in p-InSb using epitaxial p{sup +} contacts. United States. doi:10.1134/S1063782616080108.
Eminov, Sh. O., E-mail: shikhamirem@gmail.com. Mon . "Study of the impurity photoconductivity in p-InSb using epitaxial p{sup +} contacts". United States. doi:10.1134/S1063782616080108.
@article{osti_22649731,
title = {Study of the impurity photoconductivity in p-InSb using epitaxial p{sup +} contacts},
author = {Eminov, Sh. O., E-mail: shikhamirem@gmail.com},
abstractNote = {The optical absorption coefficient α in p{sup +}-InSb layers (with hole concentrations of p ≈ 1 × 10{sup 17}–1.2 × 10{sup 19} cm{sup –3}), grown by liquid-phase epitaxy on p-InSb substrates, is measured in the spectral range of 5-12 µm at 90 K, and the impurity photoconductivity is measured (at 60 and 90 K) in p{sup +}–p structures. It is found that a in the p{sup +} layers reaches a value of 7000 cm{sup –1} (at p ≈ 2 × 10{sup 19} cm{sup –1}). It is shown that the measured substrate value of (α ≈1–3 cm{sup –1}) is overestimated in comparison with estimates (α ≈ 0.1 cm{sup –1}) based on comparing the photoconductivity data. This discrepancy is explained by the fact that the optical transitions of holes responsible for photoconductivity are obscured by the excitation of electrons to the conduction band. The photoionization cross section for these transitions does not exceed 1 × 10{sup –15} cm{sup 2}.},
doi = {10.1134/S1063782616080108},
journal = {Semiconductors},
number = 8,
volume = 50,
place = {United States},
year = {Mon Aug 15 00:00:00 EDT 2016},
month = {Mon Aug 15 00:00:00 EDT 2016}
}
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