Preparation of Al-doped ZnO thin film deposited at room temperature

Al-doped ZnO (AZO) thin films were prepared at room temperature using a novel facing targets sputtering (FTS) method. The corning glass (2948) and polyethersulfone (PES) of 200 μm in thickness were used as substrates. In the work, we evaluated the influence of O2 gas flow rate and investigated the optical, structural and electrical properties of AZO thin films as a function of O2 gas flow rate. From the results, it was found that AZO thin films oriented in the (0 0 2) direction were obtained regardless of substrate type and O2 gas flow rate. In addition, the resistivity of AZO thin film deposited on both substrates increased with the increase of O2 gas flow rate. All AZO thin films except the films deposited on glass substrate at O2 gas flow rate of 0.1 were shown an average transmittance over 80% in visible range (400–800 nm). We could obtain AZO thin films with the low resistivity (2.4 × 10−3 Ω cm:glass, 4.4 × 10−3 Ω cm:PES) and high transmittance (over 80%) under the optimal conditions.