Variable-range-hopping conduction processes in oxygen deficient polycrystalline ZnO films
Variable-range-hopping conduction processes in oxygen deficient polycrystalline ZnO films
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DOI：
10.1063/1.3357376
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发表时间：
2010-03-15
影响因子：
3.2
通讯作者：
Lin, Juhn-Jong
中科院分区：
文献类型：
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作者：
Huang, Yung-Lung;Chiu, Shao-Pin;Lin, Juhn-Jong
我们采用射频溅射沉积法制备了贫氧多晶ZnO薄膜。为了系统地研究这些样品中的电荷传输机制，在从300 K到液氦温度的宽温度范围内测量了电介电常数。我们发现，低于约100 K，可变范围跳跃（弗赫）导电过程支配的电荷输运性质。特别地，Mott弗赫传导过程在较高温度下占主导地位，而在较低温度下交叉到Efros-Shklovskii（ES）弗赫传导过程。这种交叉发生在几十开氏度的高温下。此外，电阻率的温度行为在整个弗赫导电制度从莫特型ES型过程中可以很好地描述了一个普遍的标度律。
We have fabricated oxygen deficient polycrystalline ZnO films by the rf sputtering deposition method. To systematically investigate the charge transport mechanisms in these samples, the electrical resistivities have been measured over a wide range of temperature from 300 K down to liquid-helium temperatures. We found that below about 100 K, the variable-range-hopping (VRH) conduction processes govern the charge transport properties. In particular, the Mott VRH conduction process dominates at higher temperatures, while crossing over to the Efros-Shklovskii (ES) VRH conduction process at lower temperatures. The crossover occurred at temperatures as high as a few tens degrees kelvin. Moreover, the temperature behavior of resistivity over the entire VRH conduction regime from the Mott-type to the ES-type process can be well described by a universal scaling law.