Ultraviolet electroluminescence from ordered ZnO nanorod array/p-GaN light emitting diodes

Abstract

The highly ordered and aligned ZnO nanorod arrays were grown on p-GaN substrates via a facile hydrothermal process assisted by the inverted self-assembled monolayer template, from which the ZnO nanorod/p-GaN heterojunction light emitting diodes (LEDs) were fabricated. The ZnO nanorod-based LEDs exhibit a stronger ultraviolet emission of 390 nm than the ZnO film-based counterpart, which is attributed to the low density of interfacial defects, the improved light extraction efficiency, and carrier injection efficiency through the nano-sized junctions. Furthermore, the LED with the 300 nm ZnO nanorods has a better electroluminescence performance compared with the device with the 500 nm nanorods.