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Title: Photoconductive detection of hydrogen in ZnO and rutile TiO{sub 2}

Abstract

Hydrogen donors in ZnO and rutile TiO{sub 2} are probed by means of photoconductivity and IR absorption. It is shown that the O–H bonds giving rise to the local vibrational modes (LVMs) of interstitial hydrogen at 3611 and 3290 cm{sup −1} in the case of ZnO and TiO{sub 2}, respectively, also occur in the photoconductivity spectra as Fano resonances. The effects of isotope substitution, concentration, sample thickness, influence of other donors present in both oxides are considered. Based on the shape and frequency of these resonances, it is concluded that the apparent ionization energy of interstitial hydrogen in rutile TiO{sub 2} is less than 300 meV. By a direct comparison, we also demonstrate that photoconductive detection of LVMs of defects in thin semiconductor films is superior to the standard IR absorption.

Authors:
;  [1];  [2]
  1. Technische Universität Dresden, 01062 Dresden (Germany)
  2. Freie Universität Berlin, 14195 Berlin (Germany)
Publication Date:
OSTI Identifier:
22597744
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 5; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABSORPTION; COMPARATIVE EVALUATIONS; CONCENTRATION RATIO; DETECTION; HYDROGEN; IONIZATION; ISOTOPES; MEV RANGE 100-1000; PHOTOCONDUCTIVITY; RESONANCE; RUTILE; SEMICONDUCTOR MATERIALS; SPECTRA; THICKNESS; TITANIUM OXIDES; ZINC OXIDES

Citation Formats

Lavrov, E. V., E-mail: edward.lavrov@physik.tu-dresden.de, Mchedlidze, T., and Herklotz, F.. Photoconductive detection of hydrogen in ZnO and rutile TiO{sub 2}. United States: N. p., 2016. Web. doi:10.1063/1.4960132.
Lavrov, E. V., E-mail: edward.lavrov@physik.tu-dresden.de, Mchedlidze, T., & Herklotz, F.. Photoconductive detection of hydrogen in ZnO and rutile TiO{sub 2}. United States. doi:10.1063/1.4960132.
Lavrov, E. V., E-mail: edward.lavrov@physik.tu-dresden.de, Mchedlidze, T., and Herklotz, F.. 2016. "Photoconductive detection of hydrogen in ZnO and rutile TiO{sub 2}". United States. doi:10.1063/1.4960132.
@article{osti_22597744,
title = {Photoconductive detection of hydrogen in ZnO and rutile TiO{sub 2}},
author = {Lavrov, E. V., E-mail: edward.lavrov@physik.tu-dresden.de and Mchedlidze, T. and Herklotz, F.},
abstractNote = {Hydrogen donors in ZnO and rutile TiO{sub 2} are probed by means of photoconductivity and IR absorption. It is shown that the O–H bonds giving rise to the local vibrational modes (LVMs) of interstitial hydrogen at 3611 and 3290 cm{sup −1} in the case of ZnO and TiO{sub 2}, respectively, also occur in the photoconductivity spectra as Fano resonances. The effects of isotope substitution, concentration, sample thickness, influence of other donors present in both oxides are considered. Based on the shape and frequency of these resonances, it is concluded that the apparent ionization energy of interstitial hydrogen in rutile TiO{sub 2} is less than 300 meV. By a direct comparison, we also demonstrate that photoconductive detection of LVMs of defects in thin semiconductor films is superior to the standard IR absorption.},
doi = {10.1063/1.4960132},
journal = {Journal of Applied Physics},
number = 5,
volume = 120,
place = {United States},
year = 2016,
month = 8
}
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