Improvement of the electroluminescence performance of ZnO nanorods/p-GaN light emitting diodes with a ZnO films interlayer

Abstract

Heterostructure light-emitting diodes (LEDs) were fabricated by growing ZnO nanorods and undoped ZnO films on p-GaN templates. The heterojunction showed a diode-like I—V characteristic and emitted electroluminescence (EL) peaks at 383 nm, 402 nm, 438 nm, and 507 nm under forward bias. Since the electrons from ZnO nanorods and the holes from p-GaN could be injected into ZnO films with a relatively low carrier concentration and mobility, the radiative recombination was mainly confined in the ZnO film region. As a result, the ZnO nanorods/i-ZnO/p-GaN light emitting diode exhibits a stronger ultraviolet—violet emission peak.