Transient-Liquid-Phase bonding for Skutterudite-based thermoelectric modules

Kurzfassung

"Thermoelectric (TE) generators are an option for waste heat recovery in a large diversity of applications, such as automotive, aerospace or high temperature industrial processes with high energy throughput. Skutterudite materials are among the most interesting candidates for high efficiency modules in the high-temperature range up to 500 °C. However, Skutterudite-based TE modules still lack published results on reliable solutions for electrical and thermal contacts between the semiconducting TE pellets and metallic bridges and their stability under thermal treatment, leaving room for suggestions on durable joining and assembly technology. In this article we will present contacting schemes for TE couples using different diffusion barriers and a transient liquid phase (TLP) joining process. The joints have been investigated concerning their microstructure, diffusion effects and electrical contact resistivities. CrSi2 has shown suitable as anti-diffusion layer with good adhesion and electrical properties leading to contact resistivities as low as 5 µOhm·cm²."