THERMOELECTRIC CHARACTERIZATION OF BI2TE2.55SE0.45 SOLID-SOLUTION CRYSTAL

The transport properties of Bi2Te2.55Se0.45 solid solution have been m easured and described as functions of carrier concentration and temper ature. Samples were prepared using an annealing saturation technique w ithin a temperature range of 550-590 degrees C. The figure of merit is determined as a function of temperature using the Harman method. The Hall coefficient and electrical resistivity are also measured from the temperature of liquid nitrogen to room temperature. This work demonst rates that this solid solution is an extrinsic semiconductor which can be described by a band parabolic model with one carrier type. The res ults indicate that the effective mass varies with temperature and that the acoustic phonon scattering mechanism is the predominant carrier s cattering mechanism responsible for the electron diffusion. (C) 1997 E lsevier Science Ltd. All rights reserved.