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Title: Thermal evolution of defects in undoped zinc oxide grown by pulsed laser deposition

Abstract

Undoped ZnO films are grown by pulsed laser deposition on c-plane sapphire with different oxygen pressures. Thermal evolutions of defects in the ZnO films are studied by secondary ion mass spectroscopy (SIMS), Raman spectroscopy, and positron annihilation spectroscopy (PAS), and with the electrical properties characterized by the room temperature Hall measurement. Oxygen deficient defect related Raman lines 560 cm{sup −1} and 584 cm{sup −1} are identified and their origins are discussed. Thermal annealing induces extensive Zn out-diffusion at the ZnO/sapphire interface and leaves out Zn-vacancy in the ZnO film. Two types of Zn-vacancy related defects with different microstructures are identified in the films. One of them dominates in the samples grown without oxygen. Annealing the sample grown without oxygen or growing the samples in oxygen would favor the Zn-vacancy with another microstructure, and this Zn-vacancy defect persists after 1100 °C annealing.

Authors:
; ;  [1]; ;  [2]
  1. Department of Physics, The University of Hong Kong, Pokfulam Road, Hong Kong (China)
  2. Institute of Radiation Physics, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstr. 400, 01328 Dresden (Germany)
Publication Date:
OSTI Identifier:
22308912
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 3; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANNEALING; ANNIHILATION; CRYSTAL DEFECTS; DIFFUSION; ELECTRICAL PROPERTIES; ENERGY BEAM DEPOSITION; FILMS; INTERFACES; ION MICROPROBE ANALYSIS; LASER RADIATION; MASS SPECTROSCOPY; MICROSTRUCTURE; POSITRONS; PULSED IRRADIATION; RAMAN SPECTROSCOPY; SAPPHIRE; TEMPERATURE RANGE 0273-0400 K; VACANCIES; ZINC OXIDES

Citation Formats

Wang, Zilan, Su, Shichen, Ling, Francis Chi-Chung, E-mail: ccling@hku.hk, Anwand, W., and Wagner, A.. Thermal evolution of defects in undoped zinc oxide grown by pulsed laser deposition. United States: N. p., 2014. Web. doi:10.1063/1.4890460.
Wang, Zilan, Su, Shichen, Ling, Francis Chi-Chung, E-mail: ccling@hku.hk, Anwand, W., & Wagner, A.. Thermal evolution of defects in undoped zinc oxide grown by pulsed laser deposition. United States. doi:10.1063/1.4890460.
Wang, Zilan, Su, Shichen, Ling, Francis Chi-Chung, E-mail: ccling@hku.hk, Anwand, W., and Wagner, A.. Mon . "Thermal evolution of defects in undoped zinc oxide grown by pulsed laser deposition". United States. doi:10.1063/1.4890460.
@article{osti_22308912,
title = {Thermal evolution of defects in undoped zinc oxide grown by pulsed laser deposition},
author = {Wang, Zilan and Su, Shichen and Ling, Francis Chi-Chung, E-mail: ccling@hku.hk and Anwand, W. and Wagner, A.},
abstractNote = {Undoped ZnO films are grown by pulsed laser deposition on c-plane sapphire with different oxygen pressures. Thermal evolutions of defects in the ZnO films are studied by secondary ion mass spectroscopy (SIMS), Raman spectroscopy, and positron annihilation spectroscopy (PAS), and with the electrical properties characterized by the room temperature Hall measurement. Oxygen deficient defect related Raman lines 560 cm{sup −1} and 584 cm{sup −1} are identified and their origins are discussed. Thermal annealing induces extensive Zn out-diffusion at the ZnO/sapphire interface and leaves out Zn-vacancy in the ZnO film. Two types of Zn-vacancy related defects with different microstructures are identified in the films. One of them dominates in the samples grown without oxygen. Annealing the sample grown without oxygen or growing the samples in oxygen would favor the Zn-vacancy with another microstructure, and this Zn-vacancy defect persists after 1100 °C annealing.},
doi = {10.1063/1.4890460},
journal = {Journal of Applied Physics},
number = 3,
volume = 116,
place = {United States},
year = {Mon Jul 21 00:00:00 EDT 2014},
month = {Mon Jul 21 00:00:00 EDT 2014}
}
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