Sol-combustion synthesis of Al-doped ZnO transparent conductive film at low temperature

Traditional chemical methods cannot be used to synthesize flexible transparent conductive films because of their high annealing temperatures. To solve this problem, we report a novel chemical method of sol-combustion to prepare metal oxide transparent conductive films at low temperature. Al-doped ZnO thin films were synthetized by this method. The optimized synthesis conditions were discussed based on an analysis of the crystal structure, morphology, and photoelectric properties. The results show that the ratio of zinc acetate and zinc nitrate in the precursors was optimized at 5:3. The optimum Al-doping concentration was 1%. Films with good structural, electrical and optical properties were obtained at a low annealing temperature, 250 °C. Al-doped ZnO thin films with an 80% transmittance of visible light and sheet resistance of 2.4 MΩ/sq. were obtained under the optimum reaction conditions. These results indicate that the method of sol-combustion can produce AZO films at low temperature, which is a promising route to prepare other transparent conductive films at low cost.