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Information × Registration Number 0217U001019, 0114U002586 , R & D reports Title Quartz crystal resonator as an in situ method for studying of phase transformations in nano sized metal and alloy films popup.stage_title Head Sukhov Volodymir, Кандидат фізико-математичних наук Registration Date 13-01-2017 Organization Kharkov National University named after V.N. Karazin popup.description2 Object under study: single-component film of fusible metals Bi, In, Pb, Sn on an amorphous carbon support. Binary layered Bi-Sn, Bi-Ge, Au-Ge film systems on the amorphous carbon substrate and on the substrate of its own components. Multilayer Bi-Ge film systems with layers of 5-50 nm thick. Objective: solving the scientific problem of physical regularities, which governs the formation, size and thermal stability of the liquid phase in the particle-matrix systems. Finding the solution of this problem taking into account the nature of the components' interaction. Research methods: In situ method of phase transitions study in nanoscale films based on piezoquartz crystal, sequential condensation of components in ultrahigh vacuum, transmission and scanning electron microscopy, electron diffraction, X-ray spectroscopy. Size dependence of the melting-crystallization phase transitions in nanosized multilayer binary Bi-Ge film systems has been studied using in situ method based on a quartz resonator. It was found that the sensitivity of the developed method allows determining the melting and crystallization temperatures for 10-100 nm thick single-layer films on various substrates. Such result coincides with the theoretical calculations. The technique, which significantly improves the sensitivity of the method and allows studying films with thickness of less than 10 nm has been proposed. The melting and crystallization temperatures size dependencies for Bi-Ge layered film systems has been plotted in a wide range of characteristic thickness, namely 5 - 50 nm, for the first time. It has been found that the liquid phase supercooling value in the Ge/Bi/Ge system with a mass thickness of layer of 50 nm, is greater than the Bi/Ge one on about 30°C. This result has been explained by the presence of additional metal-semiconductor interface. The main results obtained for the first time, their relevance is due to both the need to understand the processes in the physics of low-dimensional systems and the widespread use of such objects in modern technologies. Results of research can be used by academic institutions engaged in similar studies. Product Description popup.authors В. М. Сухов О.Л. Самсонік О.О. Мінєнков С. В. Дукаров С.І. Богатиренко popup.nrat_date 2020-04-02 Close