Polarization switching in metal-dielectric-metal structures with polycrystalline and heteroepitaxial (Ba,Sr) TiO3 films produced by cathode sputtering

The characteristics of polarization switching are studied in metal-dielectric-metal structures as the basis of (Ba, Sr)TiO₃ films having a different degree of crystal lattice perfection. The relationships discovered support the conclusions of a phenomenological model of the spreading of the ferroelectric phase transition, according to which microvolumes of the film material are distributed by the magnitude of deformation (the sum of spontaneous deformation and induced defects) and, consequently, by the magnitude of the spontaneous polarization, Curie temperature, coercive field, etc., while the half-width of this distribution is a measure of the average microdefect. The experimentally obtained results show that the items studied have promising applications in active and permanent computer memory devices.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 28–31, April, 1986.