Tailoring electrical and optical properties of Al-doped ZnO thin films grown at room temperature by reactive magnetron co-sputtering: From band gap to near infrared

Al-doped zinc oxide (AZO) thin films were deposited at room temperature (RT) using reactive magnetron co-sputtering of two metallic Zn and Al targets in the presence of oxygen. The structural, optical and electrical properties of the AZO thin films were tailored by varying the Al content through changing Al sputtering power from 0 to 30 W. The AZO thin films deposited at the optimal deposition conditions with Al power of 26-28 W exhibited high transparency in the visible range, shorter plasma wavelength, lower electrical resistivity, lower transmittance and higher reflectance in the near IR range. The results domenstrate that the Al-doping content is strongly correlated to the band gap, electrical and near infrared optical properties using various characterization techniques. Tailoring the infrared optical properties of AZO films can be achieved and applied for desired optical coating applications.