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Information × Registration Number 0224U000924, 0123U101802 , R & D reports Title Inner size effects in nanocomposite structures as a physical basis for dual-use technology popup.stage_title Head Sukhov Volodymyr М., Кандидат фізико-математичних наук Registration Date 15-01-2024 Organization V.N. Karazin Kharkiv National University popup.description2  The first stage of the study is devoted to the establishment of physical recrystallisation of nature, during the deposition and annealing of films. Copper, silver and vanadium films with a thickness of 100 nm have been studied. It is shown that as-deposited copper films have a bimodal crystallite size distribution. This distribution is retained after annealing. By cross-sectional studies it is found that the bimodal grain size distribution is explained by the formation of localised thickenings. The height of such objects is about 50% of the film thickness. Such thickenings are to some extent isolated from the bulk of the substance. It can be considered that crystallites observed in these areas are in conditions of limited geometry. Due to this, the grains of the main film and crystallites in such localised areas evolve independently of each other. This explains the preservation of the bimodal distribution of grains after annealing. In contrast to copper films, silver samples have a layered structure. This structure provides an additional recrystallisation mechanism. By quantitative study of recrystallisation kinetics it is shown that in nanocrystalline films of copper and silver the self-diffusion coefficient increases 10-1000 times compared to the self-diffusion coefficient of bulk samples. At the same time, the growth of the diffusion coefficient in the nanoscale fraction of copper films under confined geometry is less significant than for larger grains that can grow freely. This fact may explain the low intensity of recrystallisation in vanadium films, which hardly evolve during annealing. Condensation-stimulated diffusion was found to be a more effective way to ensure recrystallisation of the films than annealing of the deposited layers. Product Description popup.authors Bohatyrenko Serhii I. Borikov Oleksii Yu Dubinin Mykola M. Dukarov Serhii V. Klochko Natalya P. Petrushenko Serhii Ivanovich Sukhov Volodymyr popup.nrat_date 2024-01-15 Close