High temperature mobility of CdTe

The Hall mobility of electrons mu (H) is measured in CdTe in the temperatur e interval 450-1050 degreesC and defined Cd overpressure in near-intrinsic conditions. The strong decrease of mu (H) above 600 degreesC is reported. T he effect is explained within a model of multivalley conduction where both electrons in Gamma (1c) minimum and in L-1c minima participate. The theoret ical description is based on the solution of the Boltzmann transport equati on within the relaxation time approximation including the polar and acousti c phonon intravalley and intervalley scatterings. The Gamma (1c) to L-1c se paration DeltaE = 0.29-10(-4)T (eV) for the effective mass in the L valley m(L) = 0.35m(0) is found to best fit the experimental data. Such DeltaE is about four times smaller than it is predicted by first-principle calculatio ns. (C) 2001 American Institute of Physics.