导电源和CdO中的化极限来源来自混合密度功能理论
Mario Burbano1, David O Scanlon, Graeme W Watson
1School of Chemistry and CRANN, Trinity College Dublin, Dublin 2, Ireland.
Journal of the American Chemical Society
|August 23, 2011
概括
这项研究揭示了氧气空缺是氧化 (CdO) 导电性的来源,解释了其n型行为. 它还证实,由于主导的n型缺陷,p型CdO是无法实现的.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 计算化学的计算化学
背景情况:
- 氧化 (CdO) 是一种众所周知的宽带间隙透明导电氧化物,具有已确定的n型导电性.
- 尽管进行了数十年的研究,但CdO电导率的确切起源以及p型电导率缺失的原因仍然不清楚.
- CdO的价值带最大值 (VBM) 相对较高,表明p型行为的潜力,但这尚未在实验中实现.
研究的目的:
- 在CdO.O.中阐明电荷载体的来源.
- 调查CdO中内在缺陷和杂质的行为.
- 为了解释p型导电性的缺乏和n型行为在CdO中的占主导地位.
主要方法:
- 使用了选混合密度函数理论 (DFT) 计算.
- 该研究的重点是分析CdO系统内的内在缺陷和杂质.
- 估计了理论上的兴奋剂极限.
主要成果:
- 在CdO中空缺的氧气被确定为浅层捐赠电荷载体的主要来源.
- 对于氧空缺,CdO不表现出负U行为,这使其与其他宽带间隙n型氧化物区别开来.
- 由于n型缺陷的流行,在所有生长条件下都无法实现p型CdO.
- 解释了通过N型兴奋剂驱动的显著的Moss-Burstein转变来实现CdO透明度的潜力.
结论:
- 该研究最终确定了CdO中n型导电性的起源,将其归因于浅层供体氧空缺.
- 研究证实不可能实现p型CdO,因为n型缺陷本质上占主导地位.
- 了解这些缺陷特性,可以通过n型兴奋剂来优化CdO的透明导电应用.
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