The effect of plastic deformation (extrusion) and subsequent annealing on the structure and thermoelectric properties of n-type Bi 2Te3-xSex and p-type Bi0.52Te3Sb1.48 system solid solution

The extrusion of n-Bi₂Te_3-xSe_x and p-Bi_0.52Te₃ Sb_1.48 solid solutions can be used not only as a form-building method but also as a means of influence on structure and thermoelectric properties of the thermoelectrics. It was determined that electrically active centers of donor origin come into existence at a condition of the extrusion under a heightened temperature (~0.7 of melting-point temperature) in the n-Bi ₂Te_3-xSe_x and p-Bi_0.52Te₃Sb_1.48 solid solutions. It is necessary to take into account this effect when manufacture of the thermoelectric with extrusion method is performed. Our research shows that the donor effect can be observed in the n-Bi₂Te_3-x Se_x and p-Bi_0.52Te₃Sb_1.48 solid solutions after plastic deformation under annealing. Analysis of the transport properties of the thermoelectrics in the combination with research of the materials structure gives a possibility to bring to light a connection of the processes at early stages of the annealing with changing of the concentration and the mobility of charge carries