Electrodeposited ZnO nanowire-based light-emitting diodes with tunable emission from near-UV to blue

Abstract

The bandgap control of doped-ZnO nanowires is important for tunable light emitting diodes (LEDs). Ultraviolet (UV), blue and violet LED structures based on Ag-doped ZnO /p-GaN and Cd-alloyed ZnO (Zn1-xCdxO) nanorods/p-GaN heterojunction have been fabricated by epitaxial electrodeposition at low temperatures and thermal annealing. UV electroluminescence (EL) peak around 397 nm observed from pure nanowires-ZnO/p-GaN at room temperature was shifted to 406 nm or 423 nm by using heterojunction between Ag-doped ZnO (ZnO:Ag) and Zn1-xCdxO-nanorods grown on p-GaN substrate, respectively. The electroluminescence emission threshold voltage was low at about 5.0 V and EL intensity increased with rise in the applied voltage bias. Presented experimental results demonstrate the tunable emission from silver and cadmium-doping in ZnO-based nanoLEDs.