Structure and Ultraviolet Electroluminescence of [Formula Omitted] Nanocomposite/[Formula Omitted] -GaN Heterostructure Light-Emitting Diodes

We fabricated and characterized ultraviolet (UV) light-emitting diodes (LEDs) composed of [Formula Omitted] nanocomposite/ [Formula Omitted]-GaN heterostructures. Significant UV electroluminescence at 387 nm from the [Formula Omitted]-ZnO layer in this heterostructure LED was observed at a forward-bias current of as low as 1.8 mA. This is ascribed to the high quality of the [Formula Omitted]-ZnO layer and the effective function of the [Formula Omitted] nanocomposite layer. The [Formula Omitted] nanocomposite layer accomplishes the role of current blocking by forming the larger energy barrier for electron injection from [Formula Omitted]-ZnO into [Formula Omitted]-GaN and also contributes to, due to its low refractive index, higher light extraction efficiency from the [Formula Omitted]-ZnO layer.