High temperature setup for measurement of Hall coefficient and electrical conductivity of thermoelectric materials.

The article focuses on the development and validation of an experimental setup for simultaneous measurement of the Hall coefficient (RH) and electrical conductivity (σ) of thermoelectric (TE) materials in the temperature range of 300–700 K. Utilizing the van der Pauw geometry, the setup features a versatile sample holder designed to accommodate typical TE specimen dimensions and enable additional measurements such as the Seebeck coefficient and thermal diffusivity on the same sample, reducing errors from inhomogeneities. Validation with doped silicon wafers demonstrated measurement precision within ±3% for RH and ±0.5% for σ, while tests on n-type Mg2Sn and p-type Mg3Sb2 thermoelectric materials confirmed the setup's applicability for heavily doped semiconductors with carrier concentrations between 10¹⁹ and 10²⁰ cm⁻³. This facility addresses challenges in high-temperature Hall effect measurements and supports research aimed at optimizing doping levels for improved thermoelectric performance.