Some Properties of HgSe–HgTe Solid Solutions

Abstract

HgTe1−xSex solid solutions have been prepared, with x varying from 0 to 1. The samples are n type near x=1 and p type near x=0, but, due to the high electron-to-hole mobility ratio, electronic conudction is dominant in the range 100–400°K in all samples. The concentration of free electrons lies between 5·1016 and 3·1018 cm−3. Measurements of the Hall mobility μH and magnetothermoelectric effect ΔQ show that, for Se-rich samples, lattice scattering is dominant in the range 77–400°K and that, near room temperature, μH ∝ T−2. For Te-rich samples, lattice scattering is dominant in the range 200–400°K and, near room temperature, μH ∝ T−1. Effective masses have been calculated and it is seen that the conduction band is not parabolic. The detailed band structure and the exact value of the mobility seem to depend little upon structural factors. For x=0.5 and x=0.9, the electron mobility can reach 12 000 cm2 v−1 sec−1 at 293°K and 30 000 cm2 v−1 sec−1 at 77°K.