Electrical effects of thallium on the Hall mobility in p-PbTe thin films

Abstract The Hall coefficient and Hall mobility were measured for epitaxial p-type PbTe films doped with thallium. It was observed that doping of the films with thallium leads to a decrease in the mobility and an increase in the concentration of charge carriers. The mobility μ D limited by defect scattering was calculated and was found to be independent of temperature and to decrease with increases in the carrier concentration p . For films with carrier concentrations exceeding 7 × 10 18 cm -3 the value of μ D decreases as p - 4 3 , whereas for films with lower carrier concentrations the decrease in μ D with p is at a slower rate.