Fairly pure ultraviolet electroluminescence from p-Si-based SiO x/ZnO/SiO x double-barrier device

Abstract

We report fairly pure ultraviolet (UV) electroluminescence (EL) from a novel p-Si-based SiO x /ZnO/SiO x ( x < 2) double-barrier device. When the device is forward biased with positive voltage applied on the gate electrode of Au film, UV light originated from the near-band-edge emission of ZnO is dominant in the EL spectra, while the defect-related visible emissions are undetectable. In the case of reverse bias, no EL is detected from the device. The mechanisms of EL and carrier transports have been explained in terms of energy band structures under forward and reverse biases.