Abstract

P-type thermoelectric material Si_0.8Ge_0.2 was sintered by Hot Press process (HP) and the effect of boron (0.25sim2 at%) addition on the thermoelectric properties were reported. To enhance the thermoelectric performances, the Si_0.8Ge_0.2, alloys were fabricated by mechanical alloying (MA) and HP. The carrier of p-type SiGe alloy was controlled by B-doping. The effect of sintering condition and thermoelectric properties were investigated. B-doped SiGe alloys exhibited positive seebeck coefficient. The electrical conductivity and thermal conductivity were increased at the small amount of boron content (0.25sim0.5 at%). However, they were decreased over 0.5 at% boron content. As a result, the small addition of boron improved the Z value. The Z value of 0.5 at% B doped Si_0.8Ge_0.2 B alloy was 0.9times10-4/K, the highest value among the prepared alloys.

• Keywords: SiGe;Thermoelectric material;HP;Thermoelectric convertor;Mechanical alloying;Hot-press;;