Effect of annealing temperatures on properties of sol-gel grown ZnO-ZrO2 films

Mixed ZnO-ZrO2 films have been obtained by sol-gel technology. By using spin coating method, the films were deposited on Si and glass substrates. The influence of thermal annealings (the temperatures vary from 400 °C to 750 °C) on their structural properties has been studied. The structural behavior has been investigated by the means of XRD and FTIR techniques. The results revealed no presence of mixed oxide phases, the detected crystal phases were related to the hexagonal ZnO and to crystalline ZrO2. The sol-gel ZnO-ZrO2 films showed polycrystalline structure with a certain degree of an amorphous fraction. The optical transmittance reached 91% and it diminished with increasing the annealing temperatures. The optical properties of the sol-gel ZnO-ZrO2 films, deposited on glass substrates are excellent with high transparency and better then those of pure ZrO2 films, obtained at similar technological conditions. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)