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Документ 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.Документ Фазовий склад та мікротвердість покриттів одержаних методом мікродугового оксидування на сплаві АЛ9(Національний технічний університет "Харківський політехнічний інститут", 2017) Харківська, Н. С.; Субботіна, Валерія ВалеріївнаДокумент Physical and technological foundations of the "Chloride" treatment of cadmium telluride layers for thin-film photoelectric converters(Сумський державний університет, 2018) Kudii, D. A.; Khrypunov, M. G.; Zaitsev, R. V.; Khrypunova, A. L.The process of deposition of cadmium chloride films during the "chloride" treatment of cadmium telluride base layers for thin-film photoelectric converters (PEC) was studied. It is established that to ensure the reproducibility of the thickness and phase composition of cadmium chloride films, it is necessary to take into account the high hygroscopicity of this material. It is shown that the optimal growth rate of cadmium chloride films is 0.1 μm perminute. At high growth rates, cadmium chloride particulates are deposited on the surface of the CdTe layer base, which causes shunting of the PEC during the "chloride" treat-ment. It is determined that after the "chloride" treatment of CdTe layers, a coarse-grained structure is observed, which is predominantly oriented in the thermodynamic equilibrium direction. In this case, the average grain size increases to 5 μm. It is shown that when performing a "chloride" treatment, the optimum purity of cadmium chloride layers is 98 %, which is due to the doping of CdTe with copper atoms. The disadvantage of copper with the use of more pure cadmium chloride reduces the efficiency of the PEC due to the increase in the series resistivity and the decrease in the photocurrent density. It has been experimentally determined that the optimum thickness of cadmium chloride during the "chloride" treatment and the efficiency of the PEC obtained at the same time depends on the substrate used. Thus, for the ITO/CdS/CdTe/Cu/Au PEC, the optimum thickness of cadmium chloride is 0.40 μm, the efficiency is 9.6 %, and for the NaCl/ITO/CdS/CdTe/Cu/Au PEC – 0.10 μm and 6.4 %, respectively.Документ Amplitude-time characteristics of switching in thin films of cadmium telluride(Сумський державний університет, 2018) Khrypunov, M. G.; Zaitsev, R. V.; Kudii, D. A.; Khrypunova, A. L.The amplitudetime characteristics of switching in thin films of cadmium telluride were investigated when single impulses of 1 μs duration are applied. It has been experimentally established that with an increase in the thickness of the cadmium telluride layer from 3 μm to 8 μm, an increase in the operating threshold from 70 V to 105 V is observed. The maximum residual sample voltage varies from 12 V to 40 V, the minimum – from 5 V to 20 V. The switching time of the samples was no more than 2 nanoseconds; the interelectrode capacity of the samples was no more than 2 pF. All the test samples were operated without failure 20 times. The structural studies of cadmium telluride films by the method of X-ray diffractometry and scanning electron microscopy have made it possible to propose a mechanism for realizing the monostable switching of the columnar structure of cadmium telluride films oriented in the form of melted high-conductivity channels in grains oriented in the direction.