Nanostructural Effect of ZnO on Light Extraction Efficiency of Near-Ultraviolet Light-Emitting Diodes

Figure 1

Schematic diagram of the process flow: (a) mesa etching after the UVLED structure growth on sapphire substrate, (b) deposition of bonding metal electrode after deposition of ITO layer onto -GaN, (c) selective deposition of thin Al layer on the ITO area using a photolithography, and (d) ZnO nanostructure growth by a hydrothermal method.

(a)

(b)

(c)

(d)