Effects of Al doping on the morphology and structure of Al-doped ZnO(AZO) were discussed. Analysis of AZO was carried out by scanning electron microscopy

photoluminescence and double-crystal X-ray diffraction. The diffraction peak position of the (002) plane was shifted to a lower angle with increasing Al concentration. It was found that the UV emission peak of near band edge emission in PL has a blue-shift to a region of higher photon energy with increasing Al concentration. The AZO epilayer was used as surface texturing

uniform current spreading

high transparent and thick window layer for achieving a highly efficient LED. AZO was deposited on the GaN-based LEDs as the transparent conducting layer. Light transmission above ~85% in the wavelength ranging from 400 to 700 nm

and AZO resistivity and roughness of ~7.3×10

-3

Ω·cm and ~28 nm were obtained

respectively. The OM image shows that the LED with an AZO layer can reach a uniform current spreading at a relatively low current intensity (~0.02 mA).