Open AccessInvestigation on strain relaxation distribution in GaN-based μLEDs by Kelvin probe force microscopy and micro-photoluminescence
Author(s) -
Jing Zhan,
Zhizhong Chen,
Qianqian Jiao,
Yue Feng,
Chengcheng Li,
Yifan Chen,
Yiyong Chen,
Fei Jiao,
Xiaoning Kang,
Shufeng Li,
Qi Wang,
Tongjun Yu,
Guoyi Zhang,
Bo Shen
Publication year - 2018
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.26.005265
Subject(s) - light emitting diode , materials science , photoluminescence , kelvin probe force microscope , optoelectronics , optics , microscopy , diode , wide bandgap semiconductor , polarization (electrochemistry) , atomic force microscopy , nanotechnology , physics , chemistry
GaN/InGaN multi-quantum-wells (MQWs) micron light emitting diodes (µLEDs) with the size ranging from 10 to 300 µm are fabricated. Effects of strain relaxation on the performance of µLEDs have been investigated both experimentally and numerically. Kelvin probe force microscopy (KPFM) and micro-photoluminescence (µPL) are used to characterize the strained area on micron pillars. Strain relaxation and reducing polarization field in MQWs almost affects the whole mesa for 10 µm LEDs and about 4% area around the lateral for 300 µm LEDs. It makes a great contribution to high performance for smaller size µLEDs. Moreover, an indirect nanoscale strain measurement for µLEDs are provided.