A study on charge transport properties of thin film Fe-doped SrTiO3 epitaxially grown on Nb-doped SrTiO3 is reported. Electric measurements between 350 °C and 750 °C show a transition from predominant ionic to electronic conduction and lower conductivity of the thin films compared to the bulk of polycrystalline samples. Defect chemical changes at elevated temperature were investigated by applying a bias voltage. A model is described which successfully predicts additional features such as inductive loops or extra semicircles measureable by impedance spectroscopy as well as the complicated time dependence of electric DC-measurements. With this model it is also possible to calculate the negligibly small ionic conductivity next to the dominating electronic conductivity in the high temperature regime. The ionic conductivity is referenced by oxygen isotope depth profiling. Changes of resistive states in Fe-doped SrTiO3 thin films at high temperature and moderate fields are compared to room temperature resistive switching phenomena at high electric fields. A conductive filament based switching process is observed at room temperature, and the capability for forming such filaments and their electric properties is further analysed using microelectrodes.

中文翻译：

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钛酸锶薄膜中的电阻态：高温和低温下的偏置效应和机制。


报道了在 Nb 掺杂 SrTiO3 上外延生长薄膜 Fe 掺杂 SrTiO3 的电荷传输特性的研究。 350 °C 至 750 °C 之间的电测量显示，与大部分多晶样品相比，薄膜的电导率从主要离子传导转变为电子传导，且电导率较低。通过施加偏压来研究高温下缺陷的化学变化。描述了一个模型，该模型成功地预测了附加特征，例如可通过阻抗谱测量的感应环或额外半圆以及电直流测量的复杂时间依赖性。利用该模型，还可以计算高温状态下仅次于主要电子电导率的可忽略不计的小离子电导率。离子电导率由氧同位素深度分析参考。将 Fe 掺杂 SrTiO3 薄膜在高温和中等电场下电阻态的变化与高电场下的室温电阻转换现象进行了比较。在室温下观察基于导电丝的切换过程，并使用微电极进一步分析形成此类丝的能力及其电性能。