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Information × Registration Number 0214U000280, 0113U002630 , R & D reports Title Quantum Size Effects in semiconducting V2VI3 and IV-VI-based Thin Film and Bulk Structures and Control of their Thermoelectric Properties popup.stage_title Head Rogacheva Elena, Доктор фізико-математичних наук Registration Date 05-02-2014 Organization The Kharkov state polytechnical university popup.description2 The subject of the research - semiconductor compound Bi2Te3 thin films with different stoichiometry deviation and lead telluride PbTe thin films alloyed with different impurities. Measurements of electroconductivity, Hall and Seebeck coefficients for all films were carried out at room temperature, kinetic coefficient dependences on film thickness were made. It was found in the first time that thin films p - Bi2Te3 kinetic coefficient dependences on film thickness in thickness range d = 20 - 100 nm has oscillation character with period d = 9.5 0.5 nm, which was associated with hole energy specter quantization. At d>~100 nm quantum oscillations fade and classical size effects, connected with diffusion scattering of charge carriers on the film surface, were observed. Theoretical interpretation of experimental data was given. Temperature dependences (77 - 300 К) of electroconductivity, Hall and Seebeck coefficients of crystal Bi2Te3 with different composition (59,6; 60,0; 60,2 та 62,8 ат. % Те) and thin films, grown on their basis are obtained. It was established that trend of ?(T) and ?H(T) for polycrystals, monocrystals and films has the same character, specified by high electron and hole gas degeneration. Kinetic coefficient temperature (77 - 300 К) and thickness dependences of thin films PbTe, alloyed by Pb and InTe, sintered on (001)KCl and (111)BaF2 substrates, was obtained. The character of T-dependence shows high electron gas degeneration and the main scattering mechanism of charge carriers is scattering on acoustic lattice vibrations. In PbTe<InTe> films change of conductivity type from р- to n-type at d ? 20 - 40 nm was observed. At d-dependences of kinetic properties of PbTe<InTe> films, grown on (001)KCl at d > 20 nm, oscillations, associated with quantum size effects, was observed. The result of theoretical calculation d is in good agreement with experimental data. Product Description popup.authors Будник Олександр Валентинович Водоріз Ольга Станіславівна Дорошенко Ганна Миколаївна Нащекіна Ольга Миколаївна Ольховська Світлана Іванівна Рогачова Олена Іванівна Сіпатов Олександр Юрійович Федоров Олександр Григорович popup.nrat_date 2020-04-02 Close