Study on anisotropy and optimization of thermoelectric properties of thermoelectric materials by a Seebeck micro-probe method

在这项研究中，一个二维塞贝克系数测量系统已开发的微探针方法和二维分布的塞贝克系数已评估各种热电材料。结果表明，各向异性的Seebeck系数反映了锌锑化物体系的晶粒分布。在铋-碲化物系统中，发现Seebeck系数从p型到n型的符号反转发生源于过量Te含量沿晶体生长方向的梯度沿着。建立了基于塞贝克微探针法的微观热电性能评价方法。塞贝克微探针法有望成为各种功能材料微观物理性质测量的新的、强有力的方法之一。

In this study, a two-dimensional Seebeck coefficient measurement system has been developed by a micro-probe method and two-dimensional distribution of Seebeck coefficient has evaluated for various thermoelectric materials. It is revealed that the anisotropic Seebeck coefficient reflecting the grain distribution in the zinc-antimonide system. In the bismuth-terullide system, it is found that the sign inversion of the Seebeck coefficient from p- to n-type occurs originating from the gradient of the excess Te content along the crystal growth direction. As a result, the evaluation method of microscopic thermoelectric properties has been established by using the Seebeck micro-probe method. It is expected that the Seebeck micro-probe method becomes one of the new and powerful ways for measurement of microscopic physical properties for various functional materials.