Lin Y H, Sun Y C, Jian W B, Chang H M, Huang Y S, Lin J J
Institute of Physics, National Chiao Tung University, Hsinchu 30010, Taiwan.
Nanotechnology. 2008 Jan 30;19(4):045711. doi: 10.1088/0957-4484/19/04/045711. Epub 2008 Jan 4.
We have studied the electrical transport properties of individual single-crystalline IrO(2) nanorods prepared by the metal-organic chemical vapour deposition method. With the help of the standard electron-beam lithographic technique, individual nanorods are contacted by Cr/Au submicron electrodes from above. Utilizing two-probe, three-probe and four-probe measurement configurations, not only the intrinsic electrical transport properties of the individual nanorods but also the electronic contact resistances, R(c)(T), have been determined from 300 K down to liquid-helium temperatures. Our measured resistivity behaviour of the nanorods is in close agreement with the current theoretical understanding of this rutile material. On the other hand, we found that the temperature behaviour of the electronic contact resistance obeys the law [Formula: see text] over an extremely wide temperature range, from approximately 100 K down to liquid-helium temperatures. This latter conduction process is ascribed to the hopping of electrons through nanoscale Cr granules and/or an amorphous coating incidentally formed at the interface between the submicron Cr/Au electrode and the nanorod.
我们研究了通过金属有机化学气相沉积法制备的单个单晶 IrO₂ 纳米棒的电输运特性。借助标准电子束光刻技术，从上方用 Cr/Au 亚微米电极接触单个纳米棒。利用两探针、三探针和四探针测量配置，不仅确定了单个纳米棒的本征电输运特性，还测定了从 300 K 到液氦温度下的电子接触电阻 Rc(T)。我们测量的纳米棒电阻率行为与目前对这种金红石材料的理论理解密切相符。另一方面，我们发现电子接触电阻的温度行为在极宽的温度范围内，从大约 100 K 到液氦温度，遵循[公式：见原文]规律。后一种传导过程归因于电子通过纳米级 Cr 颗粒和/或在亚微米 Cr/Au 电极与纳米棒之间界面偶然形成的非晶涂层的跳跃。
