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Title: Low-frequency dielectric properties of intrinsic and Al-doped rutile TiO{sub 2} thin films grown by the atomic layer deposition technique

Abstract

Dielectric spectroscopy is carried out for intrinsic and aluminum-doped TiO{sub 2} rutile films which are deposited on RuO{sub 2} by the atomic layer deposition technique. Capacitance and conductance are measured in the 0.1 Hz–100 kHz range, for ac electric fields up to 1 MV{sub rms}/cm. Intrinsic films have a much lower dielectric constant than rutile crystals. This is ascribed to the presence of oxygen vacancies which depress polarizability. When Al is substituted for Ti, the dielectric constant further decreases. By considering Al-induced modification of polarizability, a theoretical relationship between the dielectric constant and the Al concentration is proposed. Al doping drastically decreases the loss in the very low frequency part of the spectrum. However, Al doping has almost no effect on the loss at high frequencies. The effect of Al doping on loss is discussed through models of hopping transport implying intrinsic oxygen vacancies and Al related centers. When increasing the ac electric field in the MV{sub rms}/cm range, strong voltage non-linearities are evidenced in undoped films. The conductance increases exponentially with the ac field and the capacitance displays negative values (inductive behavior). Hopping barrier lowering is proposed to explain high-field effects. Finally, it is shown that Al doping strongly improves themore » high-field dielectric behavior.« less

Authors:
 [1];  [2]; ; ; ;  [1];  [3]
  1. Microelectronics Technology Laboratory (LTM), Grenoble Alpes University (UGA) and National Center for Scientific Research - CNRS, Grenoble 38000 (France)
  2. (Tunisia)
  3. LMOP, El Manar University, Tunis 2092 (Tunisia)
Publication Date:
OSTI Identifier:
22596827
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 119; Journal Issue: 24; 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; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM; CAPACITANCE; CRYSTALS; DEPOSITION; DIELECTRIC MATERIALS; DOPED MATERIALS; ELECTRIC FIELDS; LAYERS; OXYGEN; PERMITTIVITY; POLARIZABILITY; RUTHENIUM OXIDES; RUTILE; SPECTRA; THIN FILMS; TITANIUM OXIDES; VACANCIES

Citation Formats

Kassmi, M., LMOP, El Manar University, Tunis 2092, Pointet, J., Gonon, P., E-mail: patrice.gonon@cea.fr, Bsiesy, A., Vallée, C., and Jomni, F.. Low-frequency dielectric properties of intrinsic and Al-doped rutile TiO{sub 2} thin films grown by the atomic layer deposition technique. United States: N. p., 2016. Web. doi:10.1063/1.4954314.
Kassmi, M., LMOP, El Manar University, Tunis 2092, Pointet, J., Gonon, P., E-mail: patrice.gonon@cea.fr, Bsiesy, A., Vallée, C., & Jomni, F.. Low-frequency dielectric properties of intrinsic and Al-doped rutile TiO{sub 2} thin films grown by the atomic layer deposition technique. United States. doi:10.1063/1.4954314.
Kassmi, M., LMOP, El Manar University, Tunis 2092, Pointet, J., Gonon, P., E-mail: patrice.gonon@cea.fr, Bsiesy, A., Vallée, C., and Jomni, F.. Tue . "Low-frequency dielectric properties of intrinsic and Al-doped rutile TiO{sub 2} thin films grown by the atomic layer deposition technique". United States. doi:10.1063/1.4954314.
@article{osti_22596827,
title = {Low-frequency dielectric properties of intrinsic and Al-doped rutile TiO{sub 2} thin films grown by the atomic layer deposition technique},
author = {Kassmi, M. and LMOP, El Manar University, Tunis 2092 and Pointet, J. and Gonon, P., E-mail: patrice.gonon@cea.fr and Bsiesy, A. and Vallée, C. and Jomni, F.},
abstractNote = {Dielectric spectroscopy is carried out for intrinsic and aluminum-doped TiO{sub 2} rutile films which are deposited on RuO{sub 2} by the atomic layer deposition technique. Capacitance and conductance are measured in the 0.1 Hz–100 kHz range, for ac electric fields up to 1 MV{sub rms}/cm. Intrinsic films have a much lower dielectric constant than rutile crystals. This is ascribed to the presence of oxygen vacancies which depress polarizability. When Al is substituted for Ti, the dielectric constant further decreases. By considering Al-induced modification of polarizability, a theoretical relationship between the dielectric constant and the Al concentration is proposed. Al doping drastically decreases the loss in the very low frequency part of the spectrum. However, Al doping has almost no effect on the loss at high frequencies. The effect of Al doping on loss is discussed through models of hopping transport implying intrinsic oxygen vacancies and Al related centers. When increasing the ac electric field in the MV{sub rms}/cm range, strong voltage non-linearities are evidenced in undoped films. The conductance increases exponentially with the ac field and the capacitance displays negative values (inductive behavior). Hopping barrier lowering is proposed to explain high-field effects. Finally, it is shown that Al doping strongly improves the high-field dielectric behavior.},
doi = {10.1063/1.4954314},
journal = {Journal of Applied Physics},
number = 24,
volume = 119,
place = {United States},
year = {Tue Jun 28 00:00:00 EDT 2016},
month = {Tue Jun 28 00:00:00 EDT 2016}
}
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