Structural and optoelectronic properties of AZO thin films prepared by RF magnetron sputtering at room temperature
(1. College of Materials and Chemical Engineering, China Three Gorges University, Yichang 443002, China;
2. Guangxi Key Laboratory of New Energy and Building Energy Saving,
Guilin University of Technology, Guilin 541004, China)
2. Guangxi Key Laboratory of New Energy and Building Energy Saving,
Guilin University of Technology, Guilin 541004, China)
Abstract: Al-doped ZnO thin films were prepared on glass substrate using an ultra-high density target by RF magnetron sputtering at room temperature. The microstructure, surface morphology, optical and electrical properties of AZO thin films were investigated by X-ray diffractometer, scanning electron microscope, UV-visible spectrophotometer, four-point probe method, and Hall-effect measurement system. The results showed that all the films obtained were polycrystalline with a hexagonal structure and average optical transmittance of AZO thin films was over 85 % at different sputtering powers. The sputtering power had a great effect on optoelectronic properties of the AZO thin films, especially on the resistivity. The lowest resistivity of 4.5×10-4 Ω·cm combined with the transmittance of 87.1% was obtained at sputtering power of 200 W. The optical band gap varied between 3.48 and 3.68 eV.
Key words: AZO thin film; microstructure; optoelectronic properties; RF magnetron sputtering