Electrical characteristics of sol-gel derived aluminum doped zinc oxide thin films at different annealing temperatures

Aluminum (Al) doped zinc oxide (ZnO) thin films with doping concentration of 1 at.% have been prepared using sol-gel spin-coating method. Annealing process has been applied on the prepared thin films at temperatures between 350 and 500 °C. The thin films were characterized using X-ray diffractometer (XRD), UV-Vis-NIR spectrophotometer and current voltage (I-V) measurement system for structural, optical and electrical properties characterization, respectively. XRD pattern reveals the improvement of c-axis orientation with annealing temperatures. The Urbach energy as calculated from transmittance spectra increased with annealing temperatures. I-V measurement results revealed improvement in electrical properties of the thin films with annealing temperatures.