Electroluminescence from solution grown n-ZnO nanorod/p-GaN- heterostructured light emitting diodes

To fabricate n-ZnO nanorod/p-GaN-heterostructured light emitting diodes, well-aligned ZnO nanorod arrays were synthesized on metallorganic chemical vapor deposited p-GaN layers on sapphire substrates using low temperature and low cost solution growth techniques. Current-voltage measurements showed the formation of a diode structure with a typical diode characteristic having a turn-on voltage of 4.8 V. Microstructure and room-temperature photoluminescence measurements confirmed the growth of ZnO nanorod arrays with a near-perfect microstructure, stoichiometry, and excellent optical quality. Room-temperature electroluminescence in the blue-violet region with a peak wavelength of ∼398 nm was observed under a forward bias. No defect-related emission was observed in the deep visible region.