Microstructure and ferroelectric properties of epitaxial BaTiO_3/SrRuO_3/SrTiO_3 (001) films grown by pulsed laser deposition under high oxygen pressure

摘要

BaTiO_3 films were epitaxially grown on SrTiO_3 (001) substrates buffered with SrRuO_3 films as bottom elec trode by pulsed laser deposition under high O_xygen pressure of 30 Pa. The quality of the BaTiO_3/SrRuO_3/ SrTiO_3 multilayer films was analyzed by means of X-ray diffraction, atomic force microscopy and trans mission electron microscopy. BaTiO_3 films were found to be highly c-axis-oriented tetragonal phase with c/a = 1.002. The dielectric constant first increased with increasing temperature, and showed a peak at the Curie temperature of about 356 K. The films had well-saturated hysteresis loops with a remnant polariza tion of 7.3 μC/cm2 and a coercive field of 29.5 kV/cm at room temperature.