Fabrication of a Silicide Thermoelectric Module Employing Fractional Factorial Design Principles

Thermoelectric modules can be used in waste heat harvesting, sensing, and cooling applications. Here, we report on the fabrication and performance of a four-leg module based on abundant silicide materials. While previously optimized Mg 2 Si 0.3 Sn 0.675 Bi 0.025 is used as the n -type leg, we employ a fractional factorial design based on the Taguchi methods mapping out a four-dimensional parameter space among Mn x-ε Mo ε Si 1.75−δ Ge δ higher manganese silicide compositions for the p -type material. The module is assembled using a scalable fabrication process, using a Cu metallization layer and a Pb-based soldering paste. The maximum power output density of 53 μW cm –2 is achieved at a hot-side temperature of 250 °C and a temperature difference of 100 °C. This low thermoelectric output is related to the high contact resistance between the thermoelectric materials and the metallic contacts, underlining the importance of improved metallization schemes for thermoelectric module assembly.