【摘要】 用PLD方法在铂金硅衬底制作了高质量的SrBi2Ta2O9 (SBT)铁电薄膜样品.在 10到 300K的低温范围,研究了SBT薄膜的电子输运特性,分析了其传导机制.结果显示在SBT铁电薄膜中存在两种导电机制.根据SBT层状结构,两种导电机制分为: 被限制在Bi O层内的内输运,和能够穿过Bi O层的外输运.首次观察到作为内传导载流子的铁电极化子的电输运行为.在SBT薄膜中铁电极化子的热激活能Ea~ 0. 0556eV.研究结果为SBT薄膜具有极低漏电流提供了一种解释.更多还原

【Abstract】 High quality SrBi 2Ta 2O 9 (SBT) ferroelectric thin films were fabricated on platinized silicon substrate by PLD. Electronic transport properties of SrBi 2Ta 2O 9 ferroelectric thin films in temperature range of 10 to 300K were studied. The conduction mechanisms in the thin films were analyzed. The results indicate the existence of two conduction mechanisms in SBT ferroelectric thin films. Due to the SBT layered structure, the carrier transport can be divided into two parts: internal transport, which is between the (Bi 2O 2) 2+ layers, and external transport, which is across the (Bi 2O 2) 2+ layers. Especially, behavior of electric transport of the polaron as an internal transport carrier is first observed in the SrBi 2Ta 2O 9 ferroelectric thin films. Activation energy of the internal transport carriers is E a ~ 0.0556 eV. The results can be helpful in understanding the low DC leakage in SBT films at room temperature.更多还原