Ultraviolet electroluminescence of ZnO based heterojunction light emitting diode
Abstract
ZnO/GaN p-i-n heterojunctions light emitting diodes were fabricated by plasma-assisted molecular beam epitaxy. We make use of high resistivity of nitrogen doped ZnO to fabricate n-ZnO/i-ZnO/p-GaN heterojunction light emitting diode. The emission of i-ZnO was obtained due to the limitation effect of i-ZnO on electrons and holes. Moreover, n-ZnO/i-MgO/p-GaN heterojunction light emitting diode was also fabricated. The limitation effect on electrons is increased in this heterojunction. The bright ultraviolet electroluminescence at 382 nm originating from the ZnO layer was observed in the room temperature electroluminescence spectrum. We hope to realize the stimulated emission of ZnO using these heterojunctions by the improvement of crystal quality and the optimization of device structure. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
