Electron mobility and low-field transverse physical magnetoresistance were measured in Te-doped GaSb layers grown by molecular beam epitaxy. The samples investigated had electron densities ranging from 1016 to 1018 cm-3; measurements were taken in the 8-300 K temperature range. The high mobility values demonstrate that SnTe can be used as a source of Te doping with results comparable with GaTe. A detailed analysis of the magnetoresistance data demonstrates that in samples with high electron density (n & 1018 cm-3) the magnetoresistance is mainly due to mixed conduction of electrons in both Γ and L conduction band minima: the analysis gives the temperature dependence of the μΓ and μL mobilities and of the EL - EΓ energy separation between L and Γ edges. EL - EΓ is 82 meV at 300 K and 67 meV at 8 K and exhibits a non-monotonic behaviour within the temperature range explored. In samples with low electron density (n ≈ 1016 cm-3) the magnetoresistance is mainly due to the energy distribution of carriers in the Γ valley.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Materials Chemistry