Electroluminescence from ZnO nanorod/unetched GaN LED wafers under forward and reverse biases

ZnO nanorods have been prepared by a hydrothermal method on an unetched GaN-based light-emitting diode (LED) wafer. Without any etching steps or complex lithography, high brightness LED devices have been fabricated. The devices exhibited lighting up under both forward and reverse biases, and the electroluminescence spectra were dominated by GaN multiquantum well emission. Compared with that from a conventional GaN LED, the light output intensity was enhanced by the ZnO nanorods.