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Title: On the role of diluted magnetic cobalt-doped ZnO electrodes in efficiency improvement of InGaN light emitters

Abstract

The 120-nm-thick cobalt-doped ZnO (Co-doped ZnO, CZO) dilute magnetic films deposited by pulsed laser deposition were employed as the n-electrodes for both lateral-type blue (450 nm) and green (520 nm) InGaN light emitters. In comparison to the conventional blue and green emitters, there were 15.9% and 17.7% enhancements in the output power (@350 mA) after fabricating the CZO n-electrode on the n-GaN layer. Observations on the role of CZO n-electrodes in efficiency improvement of InGaN light emitters were performed. Based on the results of Hall measurements, the carrier mobilities were 176 and 141 cm{sup 2}/V s when the electrons passed through the n-GaN and the patterned-CZO/n-GaN, respectively. By incorporating the CZO n-electrode into the InGaN light emitters, the electrons would be scattered because of the collisions between the magnetic atoms and the electrons as the device is driven, leading to the reduction of the electron mobility. Therefore, the excessively large mobility difference between electron and hole carriers occurred in the conventional InGaN light emitter can be efficiently decreased after preparing the CZO n-electrode on the n-GaN layer, resulting in the increment of carrier recombination rate and the improvement of light output power.

Authors:
;  [1];  [2];  [1];  [3];  [3]
  1. Department of Materials Science and Engineering, National Chung Hsing University, Taichung 40227, Taiwan (China)
  2. Department of Materials Science and Engineering, Da-Yeh University, Changhua 51591, Taiwan (China)
  3. (China)
Publication Date:
OSTI Identifier:
22590590
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 2; 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; CARRIER MOBILITY; DOPED MATERIALS; EFFICIENCY; ELECTRODES; ELECTRON MOBILITY; ENERGY BEAM DEPOSITION; EQUIPMENT; GALLIUM NITRIDES; LASER RADIATION; LASERS; LAYERS; PULSED IRRADIATION; VISIBLE RADIATION; ZINC OXIDES

Citation Formats

Liu, Hong-Ru, Wang, Shih-Yin, Ou, Sin-Liang, Wuu, Dong-Sing, E-mail: dsw@dragon.nchu.edu.tw, Department of Materials Science and Engineering, Da-Yeh University, Changhua 51591, Taiwan, and Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 70101, Taiwan. On the role of diluted magnetic cobalt-doped ZnO electrodes in efficiency improvement of InGaN light emitters. United States: N. p., 2016. Web. doi:10.1063/1.4955488.
Liu, Hong-Ru, Wang, Shih-Yin, Ou, Sin-Liang, Wuu, Dong-Sing, E-mail: dsw@dragon.nchu.edu.tw, Department of Materials Science and Engineering, Da-Yeh University, Changhua 51591, Taiwan, & Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 70101, Taiwan. On the role of diluted magnetic cobalt-doped ZnO electrodes in efficiency improvement of InGaN light emitters. United States. doi:10.1063/1.4955488.
Liu, Hong-Ru, Wang, Shih-Yin, Ou, Sin-Liang, Wuu, Dong-Sing, E-mail: dsw@dragon.nchu.edu.tw, Department of Materials Science and Engineering, Da-Yeh University, Changhua 51591, Taiwan, and Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 70101, Taiwan. 2016. "On the role of diluted magnetic cobalt-doped ZnO electrodes in efficiency improvement of InGaN light emitters". United States. doi:10.1063/1.4955488.
@article{osti_22590590,
title = {On the role of diluted magnetic cobalt-doped ZnO electrodes in efficiency improvement of InGaN light emitters},
author = {Liu, Hong-Ru and Wang, Shih-Yin and Ou, Sin-Liang and Wuu, Dong-Sing, E-mail: dsw@dragon.nchu.edu.tw and Department of Materials Science and Engineering, Da-Yeh University, Changhua 51591, Taiwan and Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 70101, Taiwan},
abstractNote = {The 120-nm-thick cobalt-doped ZnO (Co-doped ZnO, CZO) dilute magnetic films deposited by pulsed laser deposition were employed as the n-electrodes for both lateral-type blue (450 nm) and green (520 nm) InGaN light emitters. In comparison to the conventional blue and green emitters, there were 15.9% and 17.7% enhancements in the output power (@350 mA) after fabricating the CZO n-electrode on the n-GaN layer. Observations on the role of CZO n-electrodes in efficiency improvement of InGaN light emitters were performed. Based on the results of Hall measurements, the carrier mobilities were 176 and 141 cm{sup 2}/V s when the electrons passed through the n-GaN and the patterned-CZO/n-GaN, respectively. By incorporating the CZO n-electrode into the InGaN light emitters, the electrons would be scattered because of the collisions between the magnetic atoms and the electrons as the device is driven, leading to the reduction of the electron mobility. Therefore, the excessively large mobility difference between electron and hole carriers occurred in the conventional InGaN light emitter can be efficiently decreased after preparing the CZO n-electrode on the n-GaN layer, resulting in the increment of carrier recombination rate and the improvement of light output power.},
doi = {10.1063/1.4955488},
journal = {Applied Physics Letters},
number = 2,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
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