Articles
  • Enhanced efficiency of near-UV LEDs by surface plasmon and magnetic field effects from metal films

  • Sang-Hyun Honga, Jae-Joon Kimb, Byeong-Hyeok Kimc, Na-Yeong Kimd and Jang-Won Kange,*

  • aGIST Central Research Facilities, Gwangju Institute of Science and Technology, Gwangju 61005, South Korea
    bSchool of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 56212, South Korea
    cAdvanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeolabuk-do 61005, South Korea
    dAdvanced Photonics Research Institute, Gwangju Institute of Science and Technology, Gwangju 61005, South Korea
    eDepartment of Physics, Mokpo National University, Muan, Jeollanam-do 58554, South Korea

  • This article is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The enhanced efficiency of the near-UV (NUV) LEDs was demonstrated by the combinatory effects of surface plasmons (SP) from the Ag p-electrode and out-of-plane magnetic fields from additional Co/Pt multi-layers. By utilizing an InGaN/GaN-based NUV-LED epilayer including either 100 or 40 nm p-GaN layers, four different flip-chip LEDs were fabricated by selectively adding Co/Pt ferromagnetic multi-layers on the Ag p-electrode. NUV-LEDs with Co/Pt ferromagnetic multi-layers on 100-nm-thick p-GaN showed a 10.1% enhancement of integrated electroluminescence (EL) intensity at a forward current of 20 mA, mainly due to the out-of-plane magnetic field effect. In LEDs with a 40 nm p-GaN layer, which is consistent with the penetration depth of SP fields, a further increase of 13.8% can be achieved in the integrated EL intensity at 20 mA, resulted from the additional coupling effect with SP fields. These results indicate that the combination of Ag and Co/Pt multi-layers, as the p-electrode of flip-chip LEDs, can increase the efficiency in NUV flip-chip LEDs due to efficient couplings of SP fields and an out-of-plane magnetic field with carriers injected into quantum wells


Keywords: Surface plasmon, Magnetic field, Light-emitting Diode, Near-ultraviolet, Flip-chip

This Article

  • 2022; 23(2): 121-125

    Published on Apr 30, 2022

  • 10.36410/jcpr.2022.23.2.121
  • Received on Mar 31, 2021
  • Revised on Aug 11, 2021
  • Accepted on Aug 28, 2021

Correspondence to

  • Jang-Won Kang

  • GIST Central Research Facilities, Gwangju Institute of Science and Technology, Gwangju 61005, South Korea
    Tel : +82-61-450-2322

  • E-mail: kangjw@mokpo.ac.kr