M.V. Lomonosov Moscow State University, Moscow 119991, Russia
E.I. Slynko, and V.E. Slynko
I. Frantsevich Institute for Problems of Materials Science NAS str. Wilde, 5, Chernivtsi, 58001, Ukraine pos Анотація:
Received October 19, 2014
The crystal structure, phase and elemental composition, and galvanomagnetic properties are studied in lead telluride-based alloys with transition metal impurities (Sc, Ti, Cr, V and Fe) synthesized by the Bridgman technique. The distribution of components of solid solutions along monocrystalline ingots is determined. It is shown that an increase of the impurity content leads to the formation of regions enriched with impurity and of microscopic inclusions with compositions close to the known compounds of impurity atoms with tellurium. The p–n-inversion of the conductivity type, the metal–insulator and insulator metal–transitions, and the Fermi level pinning by deep impurity levels are observed as the impurity content is increased. The kinetics of free charge carrier concentration and the Fermi energy with doping and under variation of the matrix composition and an impurity type is compared. A general model for rearrangement of the electronic structure for the investigated alloys with doping is proposed.
PACS: 71.20.Nr Semiconductor compounds; PACS: 71.55.–i Impurity and defect levels; PACS: 72.20.My Galvanomagnetic and other magnetotransport effects.
Key words: PbTe-based alloys, transition metal impurities, galvanomagnetic effects, kinetics of changes in charge carrier concentration and Fermi energy, deep and resonant impurity levels, model of electronic structure.