The effect of substrate temperature on composition and electrophysical properties of bismuth telluride films

Bismuth telluride films were prepared by the method of discrete evaporation in open vacuum, that is without protective limiting screens. Therefore their influence on composition and properties of prepared films was completely excluded. It is shown that films with compositions similar to stoichiometric Bi2Te3 ratio, probably contain both antistructural tellurium and bismuth defects and tellurium vacancies, and can be compensated and heterogeneous with respect to charge carrier concentration. This is indicated by low values of hole mobility in them and thermo-e.m.f. coefficient, as compared to volume samples at equal concentrations of charge carrier concentrations