Influence of power and temperature on properties of sputtered AZO films

Aluminum-doped zinc oxide films (AZO) were deposited on glass substrates by magnetron sputtering. The effect of RF power and deposition temperature on wettability and optical properties of AZO films are studied in detail. The increase of RF power from 60 W to 180 W (power density from 1.54 to 4.62 W/m2) leads to evolution of (100), (002) and (101) textures of zinc oxide. The XRD results shows increased preferred orientation of (002) plane along c-axis for deposited AZO films. The grain size increases from 14 nm to 23 nm with increase of RF power from 60 W to 180 W and from 17 nm to 25 nm with increase in deposition temperature from 200 °C to 600 °C. The static and dynamic contact angle formed by water and ethylene glycol varies as a function of RF power and deposition temperature. AZO films with an optical transmission 80% to 60%, refractive index 1.49 to 1.51 and band gap values from 3.29 eV to 3.21 eV were obtained in the wavelength range of 350-800 nm. The electric resistivity varies from 3.9 × 10− 2 to 1.1 × 10− 2 Ω·cm depending upon variation of RF power and deposition temperature.