Title :
Heterostructured White Light-Emitting Diode: Nanoscale Interface Analysis and Electroluminescence Studies
Author :
Tan, Swee Tiam ; Zhao, Junliang ; Iwan, S. ; Sun, Xiao Wei ; Tang, Xiaohong ; Ye, Jiandong ; Bosman, M. ; Tang, Leijun ; Lo, Guo-Qiang ; Teo, K.L.
Author_Institution :
Inst. of Microelectron., A*STAR, Singapore, Singapore
Abstract :
n-ZnO/n-GaAs heterostructured light-emitting diodes have been fabricated by a low-cost ultrasonic spray pyrolysis technique. Nanoscale interface analysis was carried out with scanning transmission electron microscopy. An ~ 8.6-nm-thick amorphous GaAsZnInO was found in the n -ZnO/n-GaAs interface. A strong and broad white electroluminescence band centered at ~ 525 nm and a weak near-infrared emission peaked at ~ 815 nm were observed when n-GaAs was positively biased. The 815-nm emission is believed to be related to the interface layer, and the 525-nm emission is assigned to the recombination of electrons from conduction band to deep-level holes in the ZnO layer.
Keywords :
III-V semiconductors; conduction bands; deep levels; electroluminescence; gallium arsenide; light emitting diodes; scanning-transmission electron microscopy; semiconductor heterojunctions; zinc compounds; ZnO-GaAs; broad white electroluminescence band; conduction band; deep-level holes; heterostructured white light-emitting diode; interface layer; n-ZnO/n-GaAs heterostructures; nanoscale interface analysis; scanning transmission electron microscopy; ultrasonic spray pyrolysis; Amorphous materials; Charge carrier processes; Electroluminescence; Electron emission; Light emitting diodes; Scanning electron microscopy; Spontaneous emission; Spraying; Transmission electron microscopy; Zinc oxide; Heterostructures; Light-emitting diode (LED); ZnO;
Journal_Title :
Electron Devices, IEEE Transactions on
DOI :
10.1109/TED.2009.2034497