THERMOELECTRIC PROPERTIES OF (BIXSB1-X)2TE3 SINGLE-CRYSTAL SOLID-SOLUTIONS GROWN BY THE THM METHOD

From the experimental determination of the Te-rich corner of the Bi-Sb-Te phase diagram, single crystal solid solutions with compositions Bi8Sb32Te60, Bi9Sb30Te60 and Bi10Sb30Te60 have been grown using the Traveling Heater Method (T.H.M.). A thermoelectric characterization of samples of these p-type solid solutions is carried out as a function of stoichiometric deviations. Highly pure samples were prepared from single crystalline ingots using an annealing saturation technique at temperatures between 510 and 570-degrees-C. With the help of measurements of electrical and thermal conductivities and the Seebeck coefficient at room temperature, a maximum in the figure of merit Z = 3.2 x 10(-3) K-1 was determined for the solid solution with a composition Bi9Sb31Te60.