ELECTRICAL-PROPERTIES OF THE 85-PERCENT BI2TE3 15-PERCENT BI2SE3 THERMOELECTRIC-MATERIAL DOPED WITH SBI3 AND CUBR

The temperature dependences of the Seebeck coefficient, resistivity, H all coefficient, and carrier mobility of SbI3- and CuBr-doped 85% Bi2T e3-15% Bi2Se3 single crystals have been characterized at temperatures ranging from 77 to 600 K, and the degenerate temperature, scattering p arameter, bandgap energy, and the effective masses of the electron and hole have been determined. The degenerate temperature of the 85% Bi2T e3-15% Bi2Se3 alloy is 103 K, and the scattering parameter is determin ed to be 0.1. The ratio of the electron to hole mobility b (= mu(e)/mu (h)) is 1.45, and the bandgap energy E-G at 0 K Of the 85% Bi2Te3-15% Bi2Se3 alloy is 0.245 eV which is higher than E-G Of the pure Bi2Te3. The effective mass of the electron and hole in the 85% Bi2Te3-15% Bi2S e3 alloy are m(e) = 0.056 m(o) and m(h) = 0.065 m(o), respectively. (C ) 1998 Elsevier Science Ltd. All rights reserved.