Кафедра "Фізика металів і напівпровідників"

Постійне посилання колекціїhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/4703

Офіційний сайт кафедри http://web.kpi.kharkov.ua/fmp

Від 2002 року кафедра має назву "Фізика металів і напівпровідників", попередня назва – кафедра металофізики.

Кафедра металофізики організована в 1930 році у складі фізико-механічного факультету ХММІ. Деканом факультету був у ті роки видатний вчений-фізик, академік Іван Васильович Обреїмов.

Кафедра входить до складу Навчально-наукового інституту комп'ютерного моделювання, прикладної фізики та математики Національного технічного університету "Харківський політехнічний інститут". За час існування кафедрою підготовлено близько 3000 інженерів, у тому числі і для зарубіжних країн.

У складі науково-педагогічного колективу кафедри працюють: 3 доктора та 2 кандидата фізико-математичних наук; 3 співробітника мають звання професора.

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Growth and Structural Characterization of Thermally Evaporated Topological Insulator Bi2Se3 Thin Films
(NanoCOFC, 2018) Rogachova, E. I.; Fedorov, A. G.; Krivonogov, S. I.; Mateychenko, P. V.; Dobrotvorskaya, M. V.; Garbuz, Alexander G.; Sipatov, A. Yu.
Size effects and thermoelectric properties of Bi0.98Sb0.02 thin films
(Institute of Thermoelectricity National Academy of Sciences of Ukraine, 2020) Rogacheva, E. I.; Novak, K. V.; Orlova, D. S.; Nashchekina, O. N.; Sipatov, A. Yu.; Lisachuk, G. V.
The room-temperature dependences of thermoelectric properties (the Seebeck coefficient S, the electrical conductivity σ, the Hall coefficient RH, and the thermoelectric power factor P = S2·σ) on the thickness (d = 5 - 250 nm) of the Bi0.98Sb0.02 solid solution thin films grown on mica substrates by thermal evaporation in vacuum from a single source were obtained. It is shown that the monotonic component of the σ(d) dependence is well described within the framework of the Fuchs-Sondheimer theory for the classical size effect. The presence of an oscillating component in the d-dependences of σ, S, RH and S2·σ is attributed to the manifestation of the quantum size effect, and the experimentally determined period of quantum oscillations Δd = 45 ± 5 nm is in good agreement with the Δd value calculated theoretically within the framework of the model of an infinitely deep potential well. Bibl. 77, Fig. 1.
Thickness-dependent quantum oscillations of the transport properties in bismuth selenide thin films
(Elsevier, 2019) Rogacheva, E. I.; Menshikova, S. I.; Sipatov, A. Yu.; Nashchekina, O. N.
The objects of the present study were thin n-Bi2Se3 films with thicknesses d = 10–100 nm, grown by thermal evaporation of n-Bi2Se3 crystals in vacuum onto heated glass substrates. The room temperature d-dependences of the Seebeck coefficient, the Hall coefficient, and the electrical conductivity of the films exhibited an oscillatory behavior, which we attribute to quantum size effects. Such interpretation of the results is supported by the fact that experimentally determined values of the oscillation period are in quite good agreement with the theoretically calculated ones. We suggest that the large amplitude and undamped character of the oscillations in the studied range of thicknesses are connected with the topologically protected gapless surface states of Bi2Se3. The observed oscillatory character of the d-dependences of the transport coefficients should be taken into account when 2D-structures are applied in nanothermoelectricity and other fields of nanoscience and nanotechnology.
Влияние газовых молекул из атмосферы на абсорбцию водорода нанокристаллическими пористыми (V, 10 ат.% Ti)Nx пленками
(Інститут металофізики ім. Г. В. Курдюмова НАН України, 2016) Власов, В. В.; Гугля, А. Г.; Марченко, Ю. А.; Солопихина, Е. С.; Зубарев, Евгений Николаевич
В работе на примере нанокристаллического тонкоплёночного нитрида ва надия (V, 10 ат.% Ti)Nx исследованы закономерности влияния газовых молекул из остаточной атмосферы внутри вакуумной камеры на термодинамические и гравиметрические характеристики пористых абсорбентов водорода. Показано, что открытая пористая структура нанокристаллических тонких плёнок активно абсорбирует не только молекулы водорода, но и более крупные молекулы. Насыщение водородом при 20⁰С приводит к тому, что достаточно большая доля газовых молекул из остаточной а мосферы оказывается заблокированной внутри пор. Вследствие этого уменьшается абсорбционная ёмкость материала (не более 3 вес.%) и повышается температура десорбции водорода (500⁰С). Высокотемпературная активация нанопористой структуры и насыщение водородом при температуре 250⁰С способствуют понижению температуры десорбции до 275⁰С и увеличению гравиметрической ёмкости до 7 вес.%.
Structure and phase formation features of Ti-Zr-Ni quasicrystalline films under heating
(Sumy State University, 2019) Malykhin, S. V.; Kondratenko, V. V.; Kopylets, I. A. ; Surovitskiy, S. V.; Baturin, A. A.; Mikhailov, I. F.; Reshetnyak, M. V.; Borisova, S. S.; Bogdanov, Yu. S.
The paper describes the growth features of thin Ti-Zr-Ni films prepared by the method of magnetron sputtering of the targets with compositions Ti₅₃Zr₃₀Ni₁₈ and Ti₄₁Zr₃₈.₃Ni₂₀.₇ on the substrates at 300 K with subsequent annealing in vacuum. The formation peculiarities of phase composition, structure and thermal stability of quasicrystalline thin films were studied. It was established that in initial state the films were X-ray-amorphous or nanocrystalline with coherence lengths (according to Scherrer) near 1.6-1.8 nm independently on the element composition of the sputtered target. This structure is relatively stable up to the temperature 673 K when the formation of the quasi-crystalline phase begins. In the films with composition of Ti₅₃Zr₃₀Ni₁₈. It is added with an admixture of the 1/1 W-crystal approximant phase. In the films with Ti₄₁Zr₃₈.₃Ni₂₀.₇ composition, an optimal annealing temperature is between 823 K and 873 K. Additionally, for the first time, the data on the formation of 2/1 approximant crystal as an admixture phase in this system were obtained. Under annealing at the temperatures higher than 873 K, the decomposition of the quasi-crystalline and approximant phases into crystalline phases stable at higher temperatures according to the equilibrium phase diagram was established.
Features of the initial stage of the formation of Ti-Zr-Ni quasicrystalline thin films
(Sumy State University, 2020) Malykhin, S. V.; Kondratenko, V. V.; Kopylets, I. A. ; Surovitskiy, S. V.; Shipkova, I. G.; Mikhailov, I. F.; Zubarev, Evgeniy N.; Bogdanov, Yu. S.
Using the methods of X-ray diffraction, transmission and scanning microscopy, the features of the initial stage of the formation of the quasicrystalline phase in thin films of Ti-Zr-Ni are studied. The films were obtained by magnetron sputtering of a target of the composition Ti₄₁Zr₃₈.₃Ni₂₀,₇ (at. %) with deposition on substrates at T = 300 K and further vacuum annealing. It was established that immediately after deposition, the films are X-ray amorphous, nanostructured. An analysis of the radial distribution functions shows that immediately after deposition, the structural state of a disordered cluster, which is topologically close to icosahedral, prevails in the near atomic medium. It is concluded that the atoms are not arranged randomly, but form a "transitional" structure with an imperfect order like three shells of the Bergman cluster stacking using icosahedrons and dodecahedrons. Such a structure is a "prepared" nucleus for the further formation of the icosahedral phase upon heating. An analysis of the annealing results suggests that the qualitative nature of the transition from the pseudo-amorphous to the quasicrystalline phase and the scale of the transformations are determined by the annealing time and temperature, as well as by the film thickness. The smaller the thickness, the more the annealing processes are inhibited. It was shown that by annealing the films of a thickness of 6 μm or more at 500 °C for more than 28 h, single-phase quasicrystalline coatings with a quasicrystallinity parameter aq of about 0.5245 nm can be obtained.
Structural-phase changes in thin films and surface layers of Ti₄₁.₅Zr₄₁.₅Ni₁₇ alloy, stimulated by radiation-thermal impact of hydrogen plasma
(Kharkiv Institute of Physics and Technology, 2019) Malykhin, S. V.; Makhlai, V. A.; Surovitskiy, S. V.; Borisova, S. S.; Herashchenko, S. S.; Kondratenko, V. V.; Kopylets, I. A.; Baturin, A. A.; Terentyev, D.
X-ray diffraction and SEM microscopy were used to study structural and phase changes in the surface layers of a Ti₄₁.₅Zr₄₁.₅Ni₁₇ alloy bulk sample (target) and a thin film (deposited by magnetron sputtering of the target) under radiation-thermal action of pulsed hydrogen plasma with a thermal load of 0.6 MJ/m² in QSPA Kh-50 installation. It is established that the irradiation results in the formation of a two-phase state: the icosahedral quasicrystalline phase together with the phase of the 1/1 approximant crystal (W-phase). As a result of isothermal (550°C) annealing, the content of the quasicrystalline phase increases.
Structure of thermally evaporated bismuth selenide thin films
(Науково-технологічний комплекс "Інститут монокристалів", 2018) Rogacheva, E. I.; Fedorov, A. G.; Krivonogov, S. I.; Mateychenko, P. V.; Dobrotvorskay, M. V.; Garbuz, A. S.; Nashchekina, O. N.; Sipatov, A. Yu.
The Bi₂Se₃ thin films with thicknesses d = 7-420 nm were grown by thermal evaporation in vacuum of stoichiometric n-Bi₂Se₃ crystals onto heated glass substrates under optimal technological conditions determined by the authors. The growth mechanism, microstructure, and crystal structure of the prepared thin films were studied using X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and atomic force microscopy. It was established that the prepared thin films were polycrystalline, with composition close to the stoichiometric one, did not contain any phases apart from Bi₂Se₃, were of a high structural quality, and the preferential growth direction [001] corresponded to the direction of a trigonal axis C₃ in a hexagonal lattice. The films, like the initial crystal, exhibited n-type conductivity. It was shown that with increasing film thickness, the grain size and the film roughness remain practically the same at thicknesses d < 100 nm, and after that increase, reaching their saturation values at d ~ 300 nm. It follows from the results obtained in this work that using the method of thermal evaporation in vacuum from a single source, one can prepare thin n-Bi₂Se₃ films of a sufficiently high structural quality with a composition close to the stoichiometric one and the preferential growth orientation.