Annealing effects for alloys based on Sb/sub 1. 5/Bi/sub 0. 5/Te/sub 3/ solid solution

Tellurium in excess of the stoichiometric value is added to alloys based on Sb/sub 1.5/Be/sub 0.5/Te/sub 3/ solid solution to obtain the optimum carrier concentration, and part of this is segregated as a tellurium-rich eutectic at the grain boundaries. Annealing increases the thermo-emf ..cap alpha.. and resistivity rho, which is due to the tellurium in the second phase dissolving, and this acts as a donor and reduces the hole concentration. We have examined the properties of alloys made by zone melting after annealing in air at 390, 470, and 520 K.