Interface-dependent rectifying TbMnO3-based heterojunctions
Interface-dependent rectifying TbMnO3-based heterojunctions
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界面依赖性整流 TbMnO3 基异质结
DOI：
10.1063/1.3660322
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发表时间：
2011-12-01
期刊：
影响因子：
1.6
通讯作者：
Wu, Tom
中科院分区：
文献类型：
--
作者：
Cui, Yimin;Tian, Yufeng;Wu, Tom
我们报告的制造和表征的氧化物异质结组成的TbMnO 3薄膜生长在导电Nb：SrTiO 3衬底。异质结表现出丰富的整流特性，不仅取决于测量温度，而且还取决于生长温度：在300 K时，两种样品中都出现了良好的整流;在较低温度下，在700 °C下生长的样品中的整流要小得多，而在780 °C下生长的样品中，它表现出反向偏压依赖性，达到5000。关于传输机制，在高温下，在两个结的传导似乎是肖特基发射样的，表明界面处的明确的能带排列;另一方面，空间电荷限制机制决定了低温传输。此外，温度和频率依赖的电容损失数据表明，运输动力学与多个热激活弛豫过程。最后，透射电子显微镜的研究揭示了晶体质量的交界面，这被认为是决定相应的传输性能。
We report the fabrication and characterizations of oxide heterojunctions composed of TbMnO3 thin films grown on conducting Nb:SrTiO3 substrates. The heterojunctions exhibit rich rectifying characteristics, depending on not only the measurement temperature but also the growth temperature: at 300 K, good rectification appears in both samples; at lower temperatures, the rectification is much smaller in the sample grown at 700 °C, whereas it exhibits a reversed bias dependence and reaches ∼5000 in the sample grown at 780 °C. Regarding to the transport mechanism, the conduction appears to be Schottky-emission-like at high temperatures in both junctions, indicating well-defined band alignment at interface; on the other hand, the space-charge-limited mechanism dictates the low temperature transport. Furthermore, the temperature and frequency dependent capacitance-loss data suggest that the transport dynamics is associated with multiple thermally activated relaxation processes. Finally, transmission electron microscopy studies shed light on the crystalline quality of the junction interfaces, which is believed to dictate the corresponding transport properties.