Characteristics of NiO–AZO thin films deposited by magnetron co-sputtering in an O2 atmosphere

Abstract

NiO–AZO thin films were prepared by DC and RF magnetron co-sputtering (MCS) system in an O2 atmosphere. The lowest resistivity of 1.75×10−1Ωcm was obtained in the film containing 1.94mol% Al. The I–V measurements of the p–n junction ((NiO–AZO)/ITO) revealed rectifying characteristics, demonstrating that the film possess p-type conductivity. These results showed good agreement with the X-ray photoelectron spectroscopy (XPS) data by the higher bond enthalpy of Ni–O (382±16.7kJ/mol) than Zn–O (159±4kJ/mol). Moreover, the NiO–AZO films had a higher work function than NiO, highlighting the potential applications of transparent contact electrodes in Gallium nitride LEDs.