Development of Semiconductor Materials for Thermoelectric Cooling

ABSTRACT

Development of suitable materials for use in thermoelectric refrigeration is under progress. In this process the electrical resistivity and the seebeck coefficient of the solid solutions Bi₂Te₃ (80 per cent)+Bi₂Se₃ (20 per cent) and Bi₂Te₃ (26 per cent) + Sb₂Te₃ (74 per cent) as functions of AgI doping and of excess tellurium respectively have been studied.

It is concluded that the bismuth telluride-bismuth selenide solid solution with 0·2 per cent AgI doping gives the best result as a n-type leg for thermoelectric refrigeration. The bismuth telluride antimony telluride solid solution with 4 per cent excess weight of tellurium is found to give the best results for the p-type leg. The best values for (α²σ) found is 30·6 × 10⁻⁴ V/ohm cm.°C. for the n-type and 58·1 × 10⁻⁴ V/ohm cm.°C. for the p-type. Some experiments on the contact resistance between the semiconductor and a copper plate have also been made.