Annealing effects on the phase and microstructure transformations of nanocrystalline (ZrO2)1−x(Sc2O3)x (x=0.02–0.16) thin films deposited by sol–gel method

Annealing effects on the phase and microstructure transformations of the sol–gel derived nanocrystalline (ZrO2)1−x(Sc2O3)x (x=0.02–0.16) films with the thickness of 0.6 μm on Si(100) substrate were investigated by X-ray diffraction and scanning electron microscopy. At annealing temperatures below 800 °C, the presence of a tetragonal or cubic phase for all the films was yielded due to the crystallite size effect. However, at higher temperatures, the determined phase compositions of the as-deposited films support that of the Sc-doped zirconia polycrystalline. After long annealing times, the films with x=0.02 and 0.08 displayed a phase decomposition, attributed to the metastability of the Sc-doped zirconia nanocrystals. On the other hand, both increasing annealing temperature and time could induce grain growth for a given film.