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Title: Thickness effect on the structure, grain size, and local piezoresponse of self-polarized lead lanthanum zirconate titanate thin films

Abstract

Polycrystalline lanthanum lead zirconate titanate (PLZT) thin films were deposited on Pt/TiO{sub 2}/SiO{sub 2}/Si substrates to study the effects of the thickness and grain size on their structural and piezoresponse properties at nanoscale. Thinner PLZT films show a slight (100)-orientation tendency that tends to random orientation for the thicker film, while microstrain and crystallite size increases almost linearly with increasing thickness. Piezoresponse force microscopy and autocorrelation function technique were used to demonstrate the existence of local self-polarization effect and to study the thickness dependence of correlation length. The obtained results ruled out the bulk mechanisms and suggest that Schottky barriers near the film-substrate are likely responsible for a build-in electric field in the films. Larger correlation length evidence that this build-in field increases the number of coexisting polarization directions in larger grains leading to an alignment of macrodomains in thinner films.

Authors:
;  [1];  [2];  [3];  [3];  [4]
  1. Departamento de Física e Química, Faculdade de Engenharia de Ilha Solteira, UNESP—Univ. Estadual Paulista, 15385-000 Ilha Solteira, SP (Brazil)
  2. Institute for Materials Science, University Duisburg-Essen, 45141 Essen (Germany)
  3. Institute of Natural Sciences, Ural Federal University, 620000 Ekaterinburg (Russian Federation)
  4. (Portugal)
Publication Date:
OSTI Identifier:
22597735
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; CORRELATIONS; ELECTRIC FIELDS; GRAIN SIZE; LANTHANUM; LEAD; LENGTH; NANOSTRUCTURES; PLZT; POLARIZATION; POLYCRYSTALS; PZT; SCHOTTKY BARRIER DIODES; SILICA; SILICON OXIDES; SUBSTRATES; THICKNESS; THIN FILMS; TITANIUM OXIDES

Citation Formats

Melo, M., Araújo, E. B., E-mail: eudes@dfq.feis.unesp.br, Shvartsman, V. V., Shur, V. Ya., Kholkin, A. L., and Department of Physics and CICECO—Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro. Thickness effect on the structure, grain size, and local piezoresponse of self-polarized lead lanthanum zirconate titanate thin films. United States: N. p., 2016. Web. doi:10.1063/1.4960137.
Melo, M., Araújo, E. B., E-mail: eudes@dfq.feis.unesp.br, Shvartsman, V. V., Shur, V. Ya., Kholkin, A. L., & Department of Physics and CICECO—Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro. Thickness effect on the structure, grain size, and local piezoresponse of self-polarized lead lanthanum zirconate titanate thin films. United States. doi:10.1063/1.4960137.
Melo, M., Araújo, E. B., E-mail: eudes@dfq.feis.unesp.br, Shvartsman, V. V., Shur, V. Ya., Kholkin, A. L., and Department of Physics and CICECO—Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro. 2016. "Thickness effect on the structure, grain size, and local piezoresponse of self-polarized lead lanthanum zirconate titanate thin films". United States. doi:10.1063/1.4960137.
@article{osti_22597735,
title = {Thickness effect on the structure, grain size, and local piezoresponse of self-polarized lead lanthanum zirconate titanate thin films},
author = {Melo, M. and Araújo, E. B., E-mail: eudes@dfq.feis.unesp.br and Shvartsman, V. V. and Shur, V. Ya. and Kholkin, A. L. and Department of Physics and CICECO—Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro},
abstractNote = {Polycrystalline lanthanum lead zirconate titanate (PLZT) thin films were deposited on Pt/TiO{sub 2}/SiO{sub 2}/Si substrates to study the effects of the thickness and grain size on their structural and piezoresponse properties at nanoscale. Thinner PLZT films show a slight (100)-orientation tendency that tends to random orientation for the thicker film, while microstrain and crystallite size increases almost linearly with increasing thickness. Piezoresponse force microscopy and autocorrelation function technique were used to demonstrate the existence of local self-polarization effect and to study the thickness dependence of correlation length. The obtained results ruled out the bulk mechanisms and suggest that Schottky barriers near the film-substrate are likely responsible for a build-in electric field in the films. Larger correlation length evidence that this build-in field increases the number of coexisting polarization directions in larger grains leading to an alignment of macrodomains in thinner films.},
doi = {10.1063/1.4960137},
journal = {Journal of Applied Physics},
number = 5,
volume = 120,
place = {United States},
year = 2016,
month = 8
}
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