Miniaturized TEG with thermal generation of free carriers

The rising interest in low temperature heat energy conversion encourages the application of thermoelectric devices. However, conventional thermoelectric devices used in the Seebeck mode as thermoelectric generators have several shortcomings and thus are inefficient when used as a generator. Additionally, the high cost–power ratio of these modules anticipates the commercial success on a broad basis. One way to achieve better suited products is provided by miniaturization of thermoelectric devices in order to enable the use of mass production methods. But in small devices the contact effects become dominant and reduce the efficiency and power density considerably. We show that using pn‐junctions with thermal generation of free carriers offers the possibility to achieve better contact properties and thus higher efficiencies and power densities. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) Miniaturized thermoelectric devices promise to achieve a low cost solution for converting heat into electricity. But contact effects become dominant and reduce the efficiency and power density considerably in short devices. The authors show that the use of pn‐junctions with thermal generation of free carriers offers the possibility to achieve better contact properties and thus higher efficiencies and power densities.