利用微弧氧化法制备四方相BaTiO_3薄膜的结构特征及铁电性能

Structural characteristics and ferroelectric properties of tetragonal BaTiO_3 films prepared by microarc oxidation

利用微弧氧化技术在钛衬底上直接制备了四方相钛酸钡铁电薄膜。利用X射线（XRD）、HP4192A阻抗分析仪和铁电测试系统（FTS）等手段对薄膜样品的相结构、介电和铁电性能进行了研究。结果表明,工艺参数为Ba（OH）2浓度为0.5mol/L,电流密度为150mA/cm^2,温度为57℃,反应时间5-20min的薄膜主要要由四方相BaTiO3构成。在微弧氧化过程中,弧点的连续移动是形成四方相BaTiO3的主要原因。此工艺参数下薄膜的剩余极化值为0.271和-4.62μC/cm^2（Pr）,与其对应的矫顽场强度分别为20和-2.8kV/cm（Ec）。该薄膜具有良好的铁电性能。

Tetragonal BaTiO3 ferroelectric films were directly prepared on titanium substrates by DC power microarc oxidation technology （MAO）. Crystal phase, dielectric and ferroelectric properties of the films were characterized by X-ray diffraction （XRD）, HP4192A precision impedance analyzer and ferroelectric test system （FTS）. The results show that the film, which were deposited in 0.5mol/L Ba（OH）2 solution with current density of 150mA/cm^2 at 57℃ and within 10min, is composed mainly by primitive tetragonal BaTiO3. Continues moving of the microarc is the main reason of the formation of tetragonal 13aTiO3. This polarization of this film are 0.271 and--4.62μC/cm^2（Pr）, and the corresponding coercive field are 20 and --2.8kV/cm （Ec）. And the film has good ferroelectric properties.