ABSTRACTAn impact of different factors on the shape of dielectric hysteresis loop in ferroelectric thin films is discussed. They include: polycrystallinity and disorientation of polarization axis, polarization nonuniformity and depolarization fields, interface contact layer and series capacity, contact potential difference and interaction of volume impurity centers with polarization field. A comparison between models and experiment show that compromise of interface layer and space charge permits to explain all main distortions of dielectric hysteresis loop in thin films at realistic parameters of the layers. The obtained results permit to explaine the distortions of real hysteresis loop and also to obtain quality parameters of samples, which are important for improving of film preparation techniques.
