Microstructure Contact Studies for Skutterudite Thermoelectric Devices

The skutterudite/electrode thermoelectric joints were fabricated with the insertion of Ti foil by spark plasma sintering. The interfacial microstructure and reliability of joints were studied during thermal duration test. A multilayer structure, which was composed of intermetallic compounds, was observed at the CoSb 3 / Ti interface after thermal aging of 20 days. The interfacial reactions and diffusion path between CoSb 3 and Ti were discussed. The contact resistance of CoSb 3 /electrode junction was measured through four‐probe method and the thermal contact resistance was calculated based on multilayer mode measurement. Effects of the contact resistivity on the performance of CoSb 3 ‐based device were discussed.