Thin-Film Thermoelectric Module for Power Generator Applications Using a Screen-Printing Method

Abstract

A new process for fabricating a low-cost thermoelectric module using a screen-printing method has been developed. Thermoelectric properties of screen-printed ZnSb films were investigated in an effort to develop a thermoelectric module with low cost per watt. The screen-printed Zn (x) Sb(1-x) films showed a low carrier concentration and high Seebeck coefficient when x was in the range of 0.5 to 0.57 and the annealing temperature was kept below 550A degrees C. When the annealing temperature was higher than 550A degrees C, the carrier concentration of the Zn (x) Sb(1-x) films reached that of a metal, leading to a decrease of the Seebeck coefficient. In the present experiment, the optimized carrier concentration of screen-printed ZnSb was 7 x 10(18)/cm(3). The output voltage and power density of the ZnSb film were 10 mV and 0.17 mW/cm(2), respectively, at Delta T = 50 K. A thermoelectric module was produced using the proposed screen-printing approach with ZnSb and CoSb(3) as p-type and n-type thermoelectric materials, respectively, and copper as the pad metal.