A microprobe technique for simultaneously measuring thermal conductivity and Seebeck coefficient of thin films
A microprobe technique for simultaneously measuring thermal conductivity and Seebeck coefficient of thin films
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DOI：
10.1063/1.3300826
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发表时间：
2010-02
影响因子：
4
通讯作者：
Yanliang Zhang;C. Hapenciuc;E. Castillo;T. Borca-Tasciuc;Rutvik J. Mehta;C. Karthik;G. Ramanath
中科院分区：
文献类型：
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作者：
Yanliang Zhang;C. Hapenciuc;E. Castillo;T. Borca-Tasciuc;Rutvik J. Mehta;C. Karthik;G. Ramanath
我们展示了一种微探针技术，可以同时测量薄膜的导热系数κ和塞贝克系数α。在这项技术中，一根由焦耳加热的v形微线作为加热器、温度计和电压电极，在与薄膜表面接触时局部加热。κ从微探针的热阻中提取，α从探针和薄膜未加热区域之间测量的塞贝克电压中提取，通过模拟探针、样品及其接触区域的传热，并通过标准参考样品进行校准。将该技术应用于掺杂硫的多孔Bi2Te3和Bi2Se3薄膜上，得到的α值分别为- 105.4和1.96 μV/K，与采用微加工测试结构独立测量得到的值相差不到2%。κ值分别为0.36和0.52 W/mK，由于膜孔隙度的影响，κ值明显低于体积值，与有效介质理论相符. ...
We demonstrate a microprobe technique that can simultaneously measure thermal conductivity κ and Seebeck coefficient α of thin films. In this technique, an alternative current joule-heated V-shaped microwire that serves as heater, thermometer and voltage electrode, locally heats the thin film when contacted with the surface. The κ is extracted from the thermal resistance of the microprobe and α from the Seebeck voltage measured between the probe and unheated regions of the film by modeling heat transfer in the probe, sample and their contact area, and by calibrations with standard reference samples. Application of the technique on sulfur-doped porous Bi2Te3 and Bi2Se3 films reveals α=−105.4 and 1.96 μV/K, respectively, which are within 2% of the values obtained by independent measurements carried out using microfabricated test structures. The respective κ values are 0.36 and 0.52 W/mK, which are significantly lower than the bulk values due to film porosity, and are consistent with effective media theory. ...