Effects of doping on the transport properties of CoSb3
Effects of doping on the transport properties of CoSb3
复制标题
DOI：
10.1063/1.371287
复制
发表时间：
1999-10-01
影响因子：
3.2
通讯作者：
Tashiro, H
中科院分区：
文献类型：
--
作者：
Anno, H;Matsubara, K;Tashiro, H
以Ni、Pd和Pt为施主杂质，系统地研究了掺杂对CoSb 3输运性质的影响。结果表明，霍尔迁移率，塞贝克系数，和电导率强烈依赖于不仅对载流子浓度，但也对这些施主杂质。我们的理论分析表明，电子有效质量和导带变形势显着影响的掺杂水平和施主杂质。CoSb 3中的这些掺杂效应可以归因于（1）电子结构随掺杂的变化和（2）导带结构的特定性质，特别是能带的非抛物线性，这可以用双带凯恩模型来解释。所观察到的掺杂的电子性质的变化也与最近的能带结构计算的CoSb 3的预测是一致的。另一方面，晶格热导率随着载流子浓度的增加而显著降低，并且几乎与施主杂质无关。基于Debye模型的分析表明，点缺陷（合金）散射与电子-声子散射的耦合对降低重掺杂n型CoSb 3的晶格热导率起着重要作用.掺杂对声子散射的影响也进行了讨论的基础上作为一个功能的电子性质和杂质的属性（原子质量和大小）的模型计算。结果表明，与有效质量和形变势密切相关的电子-晶格相互作用（电子-声子耦合）的强度是影响重掺杂n型CoSb 3中声子和载流子散射的重要因素. (C)1999年美国物理学会。[S0021- 8979（99）03319-8].
Effects of doping on the transport properties of CoSb3 have been systematically investigated using Ni, Pd, and Pt as donor impurities. It is shown that the Hall mobility, the Seebeck coefficient, and the electrical conductivity depend strongly not only on the carrier concentration but also on these donor impurities. Our theoretical analysis suggests that the electron effective mass and the conduction band deformation potential are significantly affected by both the doping levels and the donor impurities. These doping effects in CoSb3 can be attributed to (1) the changes in the electronic structure with doping and (2) the specific nature of the conduction band structure, in particular, the nonparabolicity of the band which can be explained in terms of a two-band Kane model. The observed changes in the electronic properties with doping are also consistent with the predictions of a recent band structure calculation of CoSb3. On the other hand, the lattice thermal conductivity decreases markedly with increasing carrier concentration, and is almost independent of the donor impurities. Our analysis based on the Debye model indicates that the coupling of the point-defect (alloy) scattering with the electron-phonon scattering plays an important role in reducing the lattice thermal conductivity in heavily doped n-type CoSb3. The effects of doping on the phonon scattering are also discussed on the basis of a model calculation as a function of the electronic properties and the impurity properties (atomic mass and size). As a result, it is found that the strength of the electron-lattice interaction (the electron-phonon coupling), which is closely related to the effective mass and the deformation potential, is an important factor affecting the scattering of phonons as well as charge carriers in heavily doped n-type CoSb3. (C) 1999 American Institute of Physics. [S0021- 8979(99)03319-8].