Open AccessInternal quantum efficiency and carrier dynamics in semipolar (20<span style="text-decoration: overline">21</span>) InGaN/GaN light-emitting diodes
Author(s) -
Serdal Okur,
Mohsen Nami,
Ashwin K. Rishinaramangalam,
Sang Ho Oh,
Steven P. DenBaars,
Sheng Liu,
Igal Brener,
Daniel Feezell
Publication year - 2017
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.25.002178
Subject(s) - light emitting diode , materials science , optoelectronics , quantum well , quantum efficiency , photoluminescence , diode , brightness , optics , physics , laser
The internal quantum efficiencies (IQE) and carrier lifetimes of semipolar (202¯1¯) InGaN/GaN LEDs with different active regions are measured using temperature-dependent, carrier-density-dependent, and time-resolved photoluminescence. Three active regions are investigated: one 12-nm-thick single quantum well (SQW), two 6-nm-thick QWs, and three 4-nm-thick QWs. The IQE is highest for the 12-nm-thick SQW and decreases as the well width decreases. The radiative lifetimes are similar for all structures, while the nonradiative lifetimes decrease as the well width decreases. The superior IQE and longer nonradiative lifetime of the SQW structure suggests using thick SQW active regions for high brightness semipolar (202¯1¯) LEDs.