Application of Electroless Cobalt Diffusion Barrier on Telluride-Based Low- and Middle- Temperature Range Thermoelectric Module(3/3)

This proposal will discover a new type of diffusion barrier for the Te-based thermoelectric (TE) materials. Two kinds of materials will be investigated, the low-temperature Bi2Te3 and the middle-temperature PbTe. Electroless cobalt is selected to be the barrier layer since it can minimize the growth of the porous and brittle NiTe layer. The first year of the Bi2Te3 study will focus on the deposition parameters and the thin quality on the TE materials. The growth of the intermetallic compound will be investigated. The second year will study the thermal electric properties of the TE system and the stability and failure conditions under current and temperature. The last year will discuss the joint strength when the TE material is connected with solders. The optimized conditions of the module fabrication for the low-temperature TE materials will be discussed. For the second part, the middle-temperature TE material, the first year will focus on the deposition conditions and the interface properties. In the second year, both the high- and low- temperature ends of the material that are deposited with diffusion barriers will be investigated since the bonding conditions are different. Integrated TE module will be fabricated in the last year, and the thermoelectric properties of the module will be investigated. Hopefully the results of the proposal can be beneficial to both the academic and the industry.