Sol–gel prepared ZnO: UV irradiation effect on structure and surface properties

The effect of UV irradiation on sol–gel prepared ZnO films subjected to mild thermal annealing was investigated, with special attention to their structural and surface properties. Sol–gel processes, including a high-temperature annealing stage, have been adapted to the requirements of flexible electronics for in situ synthesis of semiconductor ZnO films on polymer substrates at lower temperatures due to UV irradiation. Application of UV radiation with emission peaks at 185 and 254 nm to films annealed at 180 °C made it possible to obtain ZnO films with Zn/O ratios of ca. 1, which cannot be achieved by heat treatment alone.