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Title: Reverse-bias-driven dichromatic electroluminescence of n-ZnO wire arrays/p-GaN film heterojunction light-emitting diodes

Abstract

Position-controlled n-ZnO microwire (MW) and nanowire-bundle (NW-B) arrays were fabricated using hydrothermal growth of ZnO on a patterned p-GaN film. Both the wire/film p–n heterojunctions showed electrical rectification features at reverse-bias (rb) voltages, analogous to backward diodes. Dichromatic electroluminescence (EL) emissions with 445- and 560-nm-wavelength peaks displayed whitish-blue and greenish-yellow light from MW- and NW-B-based heterojunctions at rb voltages, respectively. The different dichromatic EL emission colors were studied based on photoluminescence spectra and the dichromatic EL peak intensity ratios as a function of the rb voltage. The different EL colors are discussed with respect to depletion thickness and electron tunneling probability determined by wire/film junction geometry and size.

Authors:
; ;  [1];  [2]; ;  [3];  [4];  [5]
  1. Faculty of Nanoscience and Advanced Materials Engineering, Graphene Research Institute, and Hybrid Materials Research Center, Sejong University, Seoul 05006 (Korea, Republic of)
  2. School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom)
  3. Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784 (Korea, Republic of)
  4. Department of Materials Science and Engineering, KAIST, Daejeon 34141 (Korea, Republic of)
  5. UNIST Central Research Facilities (UCRF), UNIST, Ulsan 44919 (Korea, Republic of)
Publication Date:
OSTI Identifier:
22594286
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 10; 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; ELECTROLUMINESCENCE; FILMS; GALLIUM NITRIDES; GEOMETRY; HETEROJUNCTIONS; LIGHT EMITTING DIODES; NANOWIRES; PHOTOLUMINESCENCE; P-N JUNCTIONS; THICKNESS; TUNNEL EFFECT; WAVELENGTHS; WIRES; ZINC OXIDES

Citation Formats

Jeong, Junseok, Choi, Ji Eun, Hong, Young Joon, E-mail: yjhong@sejong.ac.kr, Kim, Yong-Jin, Hwang, Sunyong, Kim, Jong Kyu, Kim, Sung Kyu, and Jeong, Hu Young. Reverse-bias-driven dichromatic electroluminescence of n-ZnO wire arrays/p-GaN film heterojunction light-emitting diodes. United States: N. p., 2016. Web. doi:10.1063/1.4960586.
Jeong, Junseok, Choi, Ji Eun, Hong, Young Joon, E-mail: yjhong@sejong.ac.kr, Kim, Yong-Jin, Hwang, Sunyong, Kim, Jong Kyu, Kim, Sung Kyu, & Jeong, Hu Young. Reverse-bias-driven dichromatic electroluminescence of n-ZnO wire arrays/p-GaN film heterojunction light-emitting diodes. United States. doi:10.1063/1.4960586.
Jeong, Junseok, Choi, Ji Eun, Hong, Young Joon, E-mail: yjhong@sejong.ac.kr, Kim, Yong-Jin, Hwang, Sunyong, Kim, Jong Kyu, Kim, Sung Kyu, and Jeong, Hu Young. 2016. "Reverse-bias-driven dichromatic electroluminescence of n-ZnO wire arrays/p-GaN film heterojunction light-emitting diodes". United States. doi:10.1063/1.4960586.
@article{osti_22594286,
title = {Reverse-bias-driven dichromatic electroluminescence of n-ZnO wire arrays/p-GaN film heterojunction light-emitting diodes},
author = {Jeong, Junseok and Choi, Ji Eun and Hong, Young Joon, E-mail: yjhong@sejong.ac.kr and Kim, Yong-Jin and Hwang, Sunyong and Kim, Jong Kyu and Kim, Sung Kyu and Jeong, Hu Young},
abstractNote = {Position-controlled n-ZnO microwire (MW) and nanowire-bundle (NW-B) arrays were fabricated using hydrothermal growth of ZnO on a patterned p-GaN film. Both the wire/film p–n heterojunctions showed electrical rectification features at reverse-bias (rb) voltages, analogous to backward diodes. Dichromatic electroluminescence (EL) emissions with 445- and 560-nm-wavelength peaks displayed whitish-blue and greenish-yellow light from MW- and NW-B-based heterojunctions at rb voltages, respectively. The different dichromatic EL emission colors were studied based on photoluminescence spectra and the dichromatic EL peak intensity ratios as a function of the rb voltage. The different EL colors are discussed with respect to depletion thickness and electron tunneling probability determined by wire/film junction geometry and size.},
doi = {10.1063/1.4960586},
journal = {Applied Physics Letters},
number = 10,
volume = 109,
place = {United States},
year = 2016,
month = 9
}
  • The KrF pulsed excimer laser (248 nm) and the frequency-tripled neodymium doped yttrium aluminum garnet laser (355 nm) have been used to separate GaN thin films from sapphire substrates and transfer to bond other substrate. However, these processes would increase the dislocation density, resulting in an increase of the leakage current. In this study, the effects of these two laser sources on the reverse-bias leakages of InGaN-GaN light-emitting diodes were studied.
  • In this paper, we investigate degradation of InGaN/GaN light emitting diodes (LEDs) under reverse-bias operations in water vapor and dry air. To examine failure origins, electrical characterizations including current-voltage, breakdown current profiles, optical measurement, and multiple material analyses were performed. Our findings indicate that the diffusion of indium atoms in water vapor can expedite degradation. Investigation of reverse-bias stress can help provide insight into the effects of water vapor on LEDs.
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