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Title: Optical investigations of Be doped ZnO films grown by molecular beam epitaxy

Abstract

Highlights: • The optical properties of Be doped ZnO films were investigated. • Low temperature photoluminescence spectrum was dominated by D°X and DAP emissions. • Shallow acceptor state with ionization energy of 116 meV was found in ZnO:Be films. • It is suggested that the incorporated Be atom might favor formation of Zn vacancies defects. • This work demonstrates that N doping BeZnO might be suitable for fabricating reliable p-type ZnO materials. - Abstract: In this article, the optical properties of ZnO:Be films grown by plasma-assisted molecular beam epitaxy were investigated by the excitation density-dependent and temperature-dependent photoluminescence measurements. The low temperature photoluminescence spectra showed a dominant excitons bound to neutral donors (D°X) emission centered at 3.3540 eV and strong donor-acceptor pair (DAP) transitions at 3.3000 eV. In addition, it showed that the intensity ratio of the DAP and D°X peaks changed with background electron concentration. Furthermore, a shallow acceptor state with ionization energy of 116 meV was found and attributed to Zn vacancy. The present study further suggests that Be and N codoping ZnO might be suitable for fabricating reliable p-type ZnO materials.

Authors:
 [1];  [2]; ;  [2];  [2];  [3]
  1. Faculty of Science, Jiangsu University, Zhenjiang, Jiangsu 212013 (China)
  2. State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-sen University, Guangzhou 510275 (China)
  3. (China)
Publication Date:
OSTI Identifier:
22581550
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Research Bulletin; Journal Volume: 78; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CONCENTRATION RATIO; DOPED MATERIALS; ELECTRONS; EMISSION SPECTRA; EXCITATION; EXCITONS; IONIZATION; MOLECULAR BEAM EPITAXY; OPTICAL PROPERTIES; PHOTOLUMINESCENCE; P-TYPE CONDUCTORS; TEMPERATURE DEPENDENCE; THIN FILMS; VACANCIES; ZINC OXIDES

Citation Formats

Chen, Mingming, E-mail: andychain@live.cn, Zhu, Yuan, E-mail: zhuy9@mail.sysu.edu.cn, Chen, Anqi, Shen, Zhen, Tang, Zikang, E-mail: phzktang@ust.hk, and The Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa, Macau. Optical investigations of Be doped ZnO films grown by molecular beam epitaxy. United States: N. p., 2016. Web. doi:10.1016/J.MATERRESBULL.2016.02.012.
Chen, Mingming, E-mail: andychain@live.cn, Zhu, Yuan, E-mail: zhuy9@mail.sysu.edu.cn, Chen, Anqi, Shen, Zhen, Tang, Zikang, E-mail: phzktang@ust.hk, & The Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa, Macau. Optical investigations of Be doped ZnO films grown by molecular beam epitaxy. United States. doi:10.1016/J.MATERRESBULL.2016.02.012.
Chen, Mingming, E-mail: andychain@live.cn, Zhu, Yuan, E-mail: zhuy9@mail.sysu.edu.cn, Chen, Anqi, Shen, Zhen, Tang, Zikang, E-mail: phzktang@ust.hk, and The Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa, Macau. 2016. "Optical investigations of Be doped ZnO films grown by molecular beam epitaxy". United States. doi:10.1016/J.MATERRESBULL.2016.02.012.
@article{osti_22581550,
title = {Optical investigations of Be doped ZnO films grown by molecular beam epitaxy},
author = {Chen, Mingming, E-mail: andychain@live.cn and Zhu, Yuan, E-mail: zhuy9@mail.sysu.edu.cn and Chen, Anqi and Shen, Zhen and Tang, Zikang, E-mail: phzktang@ust.hk and The Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa, Macau},
abstractNote = {Highlights: • The optical properties of Be doped ZnO films were investigated. • Low temperature photoluminescence spectrum was dominated by D°X and DAP emissions. • Shallow acceptor state with ionization energy of 116 meV was found in ZnO:Be films. • It is suggested that the incorporated Be atom might favor formation of Zn vacancies defects. • This work demonstrates that N doping BeZnO might be suitable for fabricating reliable p-type ZnO materials. - Abstract: In this article, the optical properties of ZnO:Be films grown by plasma-assisted molecular beam epitaxy were investigated by the excitation density-dependent and temperature-dependent photoluminescence measurements. The low temperature photoluminescence spectra showed a dominant excitons bound to neutral donors (D°X) emission centered at 3.3540 eV and strong donor-acceptor pair (DAP) transitions at 3.3000 eV. In addition, it showed that the intensity ratio of the DAP and D°X peaks changed with background electron concentration. Furthermore, a shallow acceptor state with ionization energy of 116 meV was found and attributed to Zn vacancy. The present study further suggests that Be and N codoping ZnO might be suitable for fabricating reliable p-type ZnO materials.},
doi = {10.1016/J.MATERRESBULL.2016.02.012},
journal = {Materials Research Bulletin},
number = ,
volume = 78,
place = {United States},
year = 2016,
month = 6
}
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