Size-dependent efficiency and efficiency droop of blue InGaN micro-light emitting diodes

Pengfei Tian, Jonathan McKendry, Zheng Gong, Benoit Jack Eloi Guilhabert, Ian Watson, Erdan Gu, Zhizhong Chen, Guoyi Zhang, Martin Dawson

Research output: Contribution to journalArticle

51 Citations (Scopus)

Abstract

The mechanisms of size-dependent efficiency and efficiency droop of blue InGaN micro-pixel light emitting diodes (LEDs) have been investigated experimentally and by simulation. Electrical characterisation confirms the improvement of current spreading for smaller LEDs, which enables the achievement of the higher efficiency at high injection current densities. Owing to the higher ratio of sidewall perimeter to mesa area of smaller LEDs, a lower efficiency was observed at a low injection current density, resulting from defect-related Shockley-Read-Hall non-radiative recombination. We demonstrate that such sidewall etch defects can be partially recovered by increased thermal annealing time, consequently improving the efficiency at low current densities
Original languageEnglish
Article number231110
Number of pages4
JournalApplied Physics Letters
Volume101
Issue number23
DOIs
Publication statusPublished - 6 Dec 2012

Fingerprint

light emitting diodes
current density
injection
defects
mesas
low currents
pixels
annealing
simulation

Keywords

  • efficiency droop
  • light-emitting diode (LED)
  • current density
  • gallium compounds

Cite this

@article{32b70d593e2643fb929ed9cef3b2c65a,
title = "Size-dependent efficiency and efficiency droop of blue InGaN micro-light emitting diodes",
abstract = "The mechanisms of size-dependent efficiency and efficiency droop of blue InGaN micro-pixel light emitting diodes (LEDs) have been investigated experimentally and by simulation. Electrical characterisation confirms the improvement of current spreading for smaller LEDs, which enables the achievement of the higher efficiency at high injection current densities. Owing to the higher ratio of sidewall perimeter to mesa area of smaller LEDs, a lower efficiency was observed at a low injection current density, resulting from defect-related Shockley-Read-Hall non-radiative recombination. We demonstrate that such sidewall etch defects can be partially recovered by increased thermal annealing time, consequently improving the efficiency at low current densities",
keywords = "efficiency droop, light-emitting diode (LED), current density, gallium compounds",
author = "Pengfei Tian and Jonathan McKendry and Zheng Gong and Guilhabert, {Benoit Jack Eloi} and Ian Watson and Erdan Gu and Zhizhong Chen and Guoyi Zhang and Martin Dawson",
year = "2012",
month = "12",
day = "6",
doi = "10.1063/1.4769835",
language = "English",
volume = "101",
journal = "Applied Physics Letters",
issn = "0003-6951",
number = "23",

}

Size-dependent efficiency and efficiency droop of blue InGaN micro-light emitting diodes. / Tian, Pengfei; McKendry, Jonathan; Gong, Zheng; Guilhabert, Benoit Jack Eloi; Watson, Ian; Gu, Erdan; Chen, Zhizhong; Zhang, Guoyi; Dawson, Martin.

In: Applied Physics Letters, Vol. 101, No. 23, 231110 , 06.12.2012.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Size-dependent efficiency and efficiency droop of blue InGaN micro-light emitting diodes

AU - Tian, Pengfei

AU - McKendry, Jonathan

AU - Gong, Zheng

AU - Guilhabert, Benoit Jack Eloi

AU - Watson, Ian

AU - Gu, Erdan

AU - Chen, Zhizhong

AU - Zhang, Guoyi

AU - Dawson, Martin

PY - 2012/12/6

Y1 - 2012/12/6

N2 - The mechanisms of size-dependent efficiency and efficiency droop of blue InGaN micro-pixel light emitting diodes (LEDs) have been investigated experimentally and by simulation. Electrical characterisation confirms the improvement of current spreading for smaller LEDs, which enables the achievement of the higher efficiency at high injection current densities. Owing to the higher ratio of sidewall perimeter to mesa area of smaller LEDs, a lower efficiency was observed at a low injection current density, resulting from defect-related Shockley-Read-Hall non-radiative recombination. We demonstrate that such sidewall etch defects can be partially recovered by increased thermal annealing time, consequently improving the efficiency at low current densities

AB - The mechanisms of size-dependent efficiency and efficiency droop of blue InGaN micro-pixel light emitting diodes (LEDs) have been investigated experimentally and by simulation. Electrical characterisation confirms the improvement of current spreading for smaller LEDs, which enables the achievement of the higher efficiency at high injection current densities. Owing to the higher ratio of sidewall perimeter to mesa area of smaller LEDs, a lower efficiency was observed at a low injection current density, resulting from defect-related Shockley-Read-Hall non-radiative recombination. We demonstrate that such sidewall etch defects can be partially recovered by increased thermal annealing time, consequently improving the efficiency at low current densities

KW - efficiency droop

KW - light-emitting diode (LED)

KW - current density

KW - gallium compounds

U2 - 10.1063/1.4769835

DO - 10.1063/1.4769835

M3 - Article

VL - 101

JO - Applied Physics Letters

JF - Applied Physics Letters

SN - 0003-6951

IS - 23

M1 - 231110

ER -