Single Crystal Growth of Bi:Sb Alloys

摘要

Bismuth is a semimetal with high electron and hole mobility. Our interest in Bi-Sb material system has recently been stimulated by promise of a new generation of thermoelectric materials based on these alloy. The crystals were grown using zone melting method with 1.0 and 1.5 cm/hour growth velocity and temperature gradient 65℃/cm. The surface was determinal on the basis of growth feature profiles under optical microscope. The features observed on the top-free surface of as-grown crystals have also been discussed. The crystals have been characterized by using the powder XRD technique. The optical absorption was measured in the wave number range 510 cm~(-1) to 4000 cm~(-1). The optical bandgap evaluated from these data, were studided and the results are discussed.