Semiconductor parameters of Bi2Te3 single crystals

Single crystals of Bi2Te3 were grown in our laboratory by a special modified Bridgman technique method and were characterized by measurements of electrical conductivity and Hall effect in two crystallographic directions (parallel and perpendicular to the c-axis). From these measurements the investigated sample was found to be p-type conductivity. The carrier concentration was evaluated as 2.64x10(17) cm(3). Also, the present investigation involves the thermoelectric power measurements of Bi2Te3 samples in the wide range 176-550 K in the two crystallographic directions. The combination of the electrical and thermal measurements in the present investigation makes it possible find various physical parameters such as diffusion coefficients, diffusion lengths, the mean free time between collision and effective masses of carriers were evaluated. The variation of the Hall mobility with temperature was studied and hence the scattering mechanism was discussed.