Semiconducting properties and band structure of MoTe2 single crystals

Abstract

Transport coefficients measurements (electrical conductivity, Hall effect, thermoelectric power) have been performed on monocrystalline MoTe2 samples in a wide temperature range (77-700 K). The samples were prepared by a based Te flux method. Experimentals results are interpreted on the basis of a p-type semi-conductor model. It has been shown that the carriers are scattered in two different ways : ionized impurities and acoustical phonons. The model here adopted is in general agreement with the band structure of the group VI transition metals dichalcogenides, with trigonal prism coordination. The dz2 band is localized in the valence band and the d xy, dx2 _ y2 band which is located at 0.98 eV from the valence band forms the bottom of the conduction band. The acceptor level located at 130 meV from the valence band may be due to a weak departure from stoichiometry