Thermoelectric arrangement having tunnel contacts

摘要

The improvement to the thermodynamic efficiency of Peltier elements and Seebeck elements is the problem addressed by the invention. It is proposed as a solution to construct a thermocouple arm from two separate semiconductor parts at different temperatures in such a way that they have a multiplicity of points where they touch one another. The two semiconductor parts have a surface coating in which electron or hole concentration is so high that the Fermi level there is situated in or very near the conduction band or valence band. There is a metallically conductive overlayer (capping layer) on these surface coatings. The points of contact between the two semiconductor parts at different temperatures are thereby tunnel contacts between the overlayers. The thickness of these surface coatings and overlayers is small by comparison with the mean free path length of the majority charge carriers in the semiconductor parts. As a result, the thermal e.m.f. of the semiconductor parts determines the thermal e.m.f. of the thermocouple arm. Since, on the other hand, the tunnel contacts between the overlayers obey the Wiedemann-Franz-Lorenz law, this combination yields an increase in the thermodynamic efficiency of the energy conversion.