An automatic apparatus with sliding probe to determine the interface resistivity for thermoelectric semiconductor

•An automatic apparatus is set up to test interface resistivity in thermoelectricity.•The digital source meter and mechatronic linear modules are operated by LabVIEW.•The probe is slid on the specimen to record voltage as a function of displacement.•Copper foam is the best boundary material to hold the specimen in place.•Peltier effect and Seebeck voltage do not induce errors of interface resistivity. Interface resistivity is one pivotal parameter that needs to be minimized in the development of thermoelectric semiconductor device for high energy efficiency. Herein an automatic apparatus to determine the interface resistivity has been established with one digital source meter and three mechatronic linear modules, and operated under the programmed LabVIEW control software. The apparatus is characteristic of the scanning probe that moves on the specimen either in the slide-mode or in the step-mode to record voltage. The sliding velocity and sampling frequency of the probe as well as the boundary materials for holding the specimen are optimized by the linearity of resistance versus displacement and the repeatability in multiple tests. The precision and resolution of the apparatus are verified, and the heterojunction specimens of Bi2Te3 or PbTe with copper are measured. The slide-mode method is compared with the step-mode in terms of the testing time and precision, and the possible error from the Peltier effect and Seebeck voltage is discussed.