Production of Si- and Ge-based thermoelectric materials by spark plasma sintering

Thermoelectric materials on the basis of SiGe produced by spark plasma sintering are studied. The degree of doping of the initial materials, the degree of mixing of Si and Ge, and the properties of the grain structure of the formed samples are varied. It is established that the use of initial materials doped with donor or acceptor impurities provides a means for controlling the charge-carrier concentration in the sintered samples. It is shown that the charge-carrier concentration has the most profound effect on the energy characteristics (power factor) of thermoelectrics. For structures with the highest charge-carrier concentration, the thermoelectric coefficients can be controlled by varying the degree of mixing of Ge and Si and the degree of uniformity of the distribution of impurities.