Effect of tellurium doping on the structural, optical, and electrical properties of CdO
Effect of tellurium doping on the structural, optical, and electrical properties of CdO
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碲掺杂对CdO结构、光学和电学性质的影响
DOI：
10.1016/j.solener.2010.05.003
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发表时间：
2010
期刊：
影响因子：
6.7
通讯作者：
A. Dakhel
中科院分区：
文献类型：
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作者：
A. Dakhel
通过真空蒸发方法在玻璃和硅片基底上制备了 Te 掺杂 CdO 薄膜（1%、3% 和 5%）。通过 X 射线荧光、X 射线衍射、UV-VIS-NIR 吸收光谱和直流电测量对制备的薄膜进行了表征。实验数据表明，Te 离子的掺杂对 CdO 晶体结构产生了轻微的应力，并改变了光学和电学性能。由于少量 (1%) 的 Te 离子掺杂，主体 CdO 的带隙突然变窄约 23%。这种带隙收缩可以通过陷阱能级与导带重叠的影响来解释。 Te掺杂CdO薄膜的电学行为表明它们是带隙为1.7-2.2eV的简并半导体。相对于未掺杂的 CdO 薄膜，1% Te 掺杂的 CdO 薄膜的迁移率提高了约 5 倍，电导率提高了约 140 倍，载流子浓度提高了约 27 倍。从透明导电氧化物的角度来看，Te对于CdO掺杂来说是足够有效的。最后，在经典德鲁德理论的框架下研究了近红外光谱区的吸收。
Te-doped CdO thin-films (1%, 3%, and 5%) have been prepared by a vacuum evaporation method on glass and silicon-wafer substrates. The prepared films were characterised by X-ray fluorescence, X-ray diffraction, UV–VIS–NIR absorption spectroscopy, and dc-electrical measurements. Experimental data indicate that Te ions doping slightly stresses the host CdO crystalline structure and changes the optical and electrical properties. The bandgap of the host CdO was suddenly narrowed by about 23% due to a little (1%) doping with Te ions. This bandgap shrinkage was explained by effects of trap levels overlapping with conduction band. The electrical behaviours of the Te-doped CdO films show that they are degenerate semiconductors with a bandgap of 1.7–2.2eV. The 1% Te-doped CdO film shows increase its mobility by about 5 times, conductivity by ∼140 times, and carrier concentration by ∼27 times, relative to undoped CdO film. From transparent-conducting-oxide point of view, Te is sufficiently effective for CdO doping. Finally, the absorption in the NIR spectral region was studied in the framework of the classical Drude theory.