The influence of the structural perfection degree on the switching processes in polycrystalline BaTiO3 thin films

Abstract Polycrystalline BaTiO, thin films of thickness dw = 0.5–5 μm were obtained by the cathode sputtering method in a radio frequency field. Depending on the technological conditions the films obtained exhibited varying degrees of perfection of the crystal structure. As the measure of degree of structural perfection of the thin films was taken the value of mean dimensions of areas of coherent X-rays scattering (D) and of mean microdeformations (Δd/d), in the direction normal to the substrate surface. With increase in (Δd/d) and decrease in D, there is a decrease in value of permittivity (e) of orientation polarization (Pr ) and residual polarization (PR ), while an increase is found in the coercive field (Ec ). in the switching time (ts ) and in degree of diffuseness of the ferroelectric phase transition. Results obtained on the relations between structure and ferroelectric properties are interpreted basing on the phenomenological model of ferroelectrics with a diffused phase transition and the dynami...