PECULIARITIES OF THE SWITCHING PROCESS IN POLYCRYSTALLINE THIN FERROELECTRIC-FILMS OF PZT TYPE

One of the basic properties of thin ferroelectric films is the ability to switch polarization under the influence of an external electric fi eld. The application of such thin films as memory devices is based on this phenomenon. The switching process of the thin films has some dist inctive features. These include, for example, the dependence of the sw itching time on the electrode surface and an anomalous variation of th e switching time curve with the amplitude of bipolar rectangular elect ric voltage impulses. To describe the physical nature of these peculia rities a simple model is developed. The qualitative compatibility betw een experiment and the model is shown on the basis of the Pb(Zr,Ti,B', B'')O3 (PZT)-type thin films with the chemical constitution Pb(Zr0.53T i0.45W0.01Cd0.01)O3.