Open AccessUV-free red electroluminescence from the cross-connected p-ZnO:Cu nanobushes/n-GaN light emitting diode
Author(s) -
Yumei Wang,
Yibo Han,
Junbo Han,
Xianghui Zhang,
Ying Chen,
Siliang Wang,
Li Wen,
Nishuang Liu,
Jun Su,
Luying Li,
Yihua Gao
Publication year - 2016
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.24.003940
Subject(s) - materials science , electroluminescence , light emitting diode , optoelectronics , photoluminescence , chemical vapor deposition , diode , heterojunction , ultraviolet , doping , green light , nanotechnology , blue light , layer (electronics)
A p-ZnO:Cu/n-GaN heterojunction light emitting diode (LED) is fabricated by growing cross-connected p-ZnO:Cu nanobushes on n-GaN film using chemical vapor deposition under oxygen-rich condition. This LED emits stable UV-free red light of 677 nm and 745 nm. The electroluminescence (EL) light of this LED is tuned from ultraviolet (UV) of ZnO/GaN to UV-free red by the electronic interfacial transition from the conduction band of n-GaN to the deep acceptor levels of p-ZnO:Cu. Both room temperature and low temperature (5K) photoluminescence spectra of ZnO:Cu indicate that the UV emission of ZnO is suppressed and the green emission is enhanced, which implies the formation of Cu-related deep levels introduced by intentionally doping Cu in ZnO. These deep levels help the EL red emission in the LED device.