Ultraviolet electroluminescence properties from devices based on n-ZnO/i-NiO/p-Si light-emitting diode

摘要

We fabricated the Ultraviolet light-emitting diode (LED) based on n-ZnO/i-NiO/p-Si heterostructure by metal-organic chemical vapor deposition (MOCVD). The device exhibited diode-like rectifying characteristics with a turn-on voltage of 3.2 V. The NiO film with high resistance state and [200] preferred orientation acted as an electron blocking layer, which produced a larger ZnO/NiO conduction band offset of 2.93 eV than that of ZnO/Si (0.30 eV). Under forward bias, prominent ultraviolet emissions peaked around 375 nm accompanying with rather weak blue-white emissions peaked around 480 nm were observed at room temperature. Furthermore, the mechanisni of the electroluminescence was tentatively discussed in terms of the band diagram of the diode. (C) 2016 Elsevier B.V. All rights reserved.