Open AccessEnhancement of wall-plug efficiency in vertical InGaN/GaN LEDs by improved current spreading
Author(s) -
Jun Ho Son,
Buem Joon Kim,
Chul Jong Ryu,
Yang Hee Song,
Hwan Keon Lee,
Joo Won Choi,
JongLam Lee
Publication year - 2012
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.20.00a287
Subject(s) - light emitting diode , materials science , chemical vapor deposition , optoelectronics , diode , transmittance , spark plug , layer (electronics) , current (fluid) , wide bandgap semiconductor , optics , composite material , electrical engineering , physics , engineering , aerospace engineering
We present the enhancement of wall-plug efficiency in vertical InGaN/GaN light-emitting diodes (V-LEDs) by improved current spreading with a novel Al2O3 current blocking layer (CBL). The Al2O3 CBL deposited by electron-beam evaporation shows high transmittance and good corrosion resistance to acidic solutions. V-LEDs with an Al2O3 CBL show similar light output power but lower forward voltage as compared to those with a SiO2 CBL deposited by plasma-enhanced chemical vapor deposition. As a result, the wall-plug efficiency of V-LEDs with an Al2O3 CBL at 500 mA was improved by 5% as compared to those with a SiO2 CBL, and by 19% as compared to those without a CBL.