Invertierungsversuche am system ZnSbCdSb

Abstract

ZnSb has some importance as a thermoelectric material for the generation of electrical power in the intermediate temperature range. Undoped ZnSb exhibits the p-type as does CdSb. But whereas CdSb may be inverted easily by elements of the third group of the periodic table, n-type ZnSb has not yet been isolated. The present authors have investigated the p → n-inversion in ZnSbCdSb alloys covering the whole concentration range. In pure ZnSb only a decrease of the hole concentration is possible. In mixed crystals of ZnSb and CdSb the inversion succeeded in CdSb rich compositions. In the medium concentration range, e.g. 50 ZnSb . 50 CdSb, the initial p → n inversion was followed by a reverse n ← p inversion in the solid phase at room temperature. The authors have studied the influence of annealing, doping element, concentration of doping element, temperature and temperature gradient along the specimen on the time of reversion from n- to p-type. In ZnSb rich alloys only a decrease of the hole concentration was obtained.