Growth of PbTe crystals for thermoelectric applications

A modified vertical Bridgman method was performed to grow PbTe single crystals for thermoelectric applications. A quartz ampoule was used as the crucible with the dimensions of 31 mm in inner diameter and 425 mm in length. PbTe was synthesized in the sealed crucible then grown at a rate of 0.1-0.3 mm/hr. The as-grown boule contained several large crystal grains and the largest size of the grain is 14 /spl times/ 22 /spl times/ 30 mm/sup 3/. The PbTe crystal has cubic structure determined by X-ray diffraction.