Inhaltszusammenfassung

We have investigated the crystal structure and the ferroelectric properties of SrBi2Nb2O9 (SBN) thin films with YBa2Cu3O7?? (YBCO) as the bottom and Au as the top electrode. Epitaxial heterostructures of YBCO and SBN were prepared by dc and rf sputtering, respectively, on SrTiO3 substrates. In a second layout we used a semiconducting Nb doped (0.05 wt?% Nb) SrTiO3 (N-STO) substrate as the bottom electrode. The crystal structure of the films was characterized by x-ray diffraction. Since the SB...We have investigated the crystal structure and the ferroelectric properties of SrBi2Nb2O9 (SBN) thin films with YBa2Cu3O7?? (YBCO) as the bottom and Au as the top electrode. Epitaxial heterostructures of YBCO and SBN were prepared by dc and rf sputtering, respectively, on SrTiO3 substrates. In a second layout we used a semiconducting Nb doped (0.05 wt?% Nb) SrTiO3 (N-STO) substrate as the bottom electrode. The crystal structure of the films was characterized by x-ray diffraction. Since the SBN films exhibit a perfect c-axis oriented growth without the (115) phase the hysteresis loop measurements do not indicate ferroelectric behavior of the SBN films. The diode with a N-STO bottom electrode reveals, for a positive and negative applied voltage, a depletion and accumulation of the carrier density, respectively. The time dependent polarization and depolarization current can be described by a power law (Curie-von Schweidler). The conductivity as a function of applied voltage can be explained by the Schottky effect.» weiterlesen» einklappen

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Klassifikation

DFG Fachgebiet:
Physik der kondensierten Materie

DDC Sachgruppe:
Physik