Two instruments implementing the van der Pauw (VDP) method for measuring the specific resistivity and Hall coefficient at high temperatures are described. Several features to minimize the measurement errors are proposed and some of the advantages compared with traditional six-probe combined resistivity and Hall coefficient measurements are outlined. The VDP method is convenient for use in thermoelectrics research since it accepts sample geometries compatible with measurements of the Seebeck coefficient and thermal diffusivity. This allows for the thermoelectric figure of merit to be measured using a single sample and without shaping the sample between measurement of individual properties. The technique is simple and can be used with samples showing a broad range of shapes and physical properties, from near insulators to metals. The two instruments are currently in use at Caltech and at Aarhus University.
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31st International and 10th European Conference on Thermoelectrics, 2012