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Документ Mechanisms of radiation damage to Sc/Si multilayer mirrors under EUV laser irradiation(IOP Publishing Ltd, 2009) Pershyn, Yuriy P.; Zubarev, Evgeniy N.; Voronov, D. L.; Sevryukova, V. A.; Kondratenko, V. V.; Vaschenko, G.; Grisham, M.; Menoni, C. S.; Rocca, J. J.; Artioukov, Y. A.; Uspenskii, Y. A.; Vinogradov, A. V.Specific structural changes in Sc/Si multilayer mirrors irradiated with extreme ultraviolet (EUV) laser single pulses (λ = 46.9 nm) at near damage threshold fluences (0.04–0.23 J cm−2) are analysed. We have identified melting of surface layers as the basic degradation mechanism for the mirrors. Both heat generation during silicide formation and low heat conduction of the layered system significantly decreases the degradation threshold of Sc/Si multilayer mirrors compared with bulk materials. The results are relevant to the use of the multilayer mirrors for shaping and directing the intense beams produced by the new generation of coherent EUV sourcesДокумент The structure of Mo/Si multilayers prepared in the conditions of ionic assistance(Springer, 2008) Zubarev, Evgeniy N.; Kondratenko, V. V.; Sevryukova, V. A.; Yulin, S. A.; Feigl, T.; Kaiser, N.The influence of a negative substrate-applied bias potential on the structure of periodic Mo/Si multilayer compositions has been investigated by means of cross-sectional electron microscopy, small-angle X-ray reflectivity, X-ray diffraction and by modeling the small-angle spectra. It is known that the crystalline structure of molybdenum layers is the main source of interface roughness. In the absence of a bias potential application, the interface roughness tends to develop from the substrate towards the surface of a Mo/Si multilayer composition. A negative bias potential (up to −200 V) applied to a substrate during silicon layer deposition leads to smoother interfaces and improves the layer morphology. After increasing the bias potential over −200 V a considerable growth of an amorphous interlayer transition zone can be observed at Si-on-Mo interfaces. By raising the bias potential during the deposition of Mo layers a development of roughness at Mo-on-Si interfaces as well as growing interlayer thicknesses were found.Документ Analysis of 46.9-nm Pulsed Laser Radiation Aftereffects in Sc/Si Multilayer X-Ray Mirrors(Springer, 2007) Pershyn, Yuriy P.; Voronov, D. L.; Zubarev, Evgeniy N.; Sevryukova, V. A.; Kondratenko, V. V.; Vaschenko, G.; Grisham, M.; Menoni, C. S.; Rocca, J. J.; Vinogradov, A. V.; Artyukov, I. A.; Uspenskii, Yu. A.Specific structural changes in Sc/Si multilayers (MLs) irradiated by nanosecond 46.9-nm single laser pulses with fluences of 0.04-5.00 J/cm2 were studied by methods of SEM and cross-sectional TEM. The threshold damage was found to be 0.08 J/cm2 The ML melts down under the fluence F >0.08 J/cm2 and the exothermic reaction of silicide formation starts. Main degradation mechanisms of MLs are discussed. The results of this study can be used for development of advanced multilayer mirrors capable handling the intense radiation conditions of new generation coherent X-ray sources.Документ Structure, thermal stability and reflectivity of Sc/Si and Sc/W/Si/W multilayer X-ray mirrors(SPIE, 2001) Vinogradov, A. V.; Pershin, Yu. P.; Zubarev, Evgeniy N.; Voronov, D. L.; Pen’kov, A. V.; Kondratenko, V. V.; Uspenskii, Yu. A.; Artioukov, I. A.; Seely, J. F.Processes going on at elevated temperatures between Sc and Si layers in Sc/Si coatings are studied by X-ray scattering and cross-sectional transmission electron microscopy. It is shown that the W layers of 0.5-0.8nm placed at Sc-Si interfaces form effective barriers preventing the penetration of Si into Sc. The effects of Si-Sc diffusion and W-barriers on the reflectivity of coatings are calculated in good agreement with experimental results. Presented measurements show that the Sc/W/Si/W multilayers with the period of 20.5 nm fabricated by dc-magnetron sputtering possess thermal stability up to 250 C and the normal incidence reflectivity of 24% at wavelengths about 40 nm.Документ Structure and mechanical stresses in TaSi 2 /Si multilayer(STC "Institute for Single Crystals", 2018) Devizenko, A. Yu.; Kopylets, I. A.; Kondratenko, V. V.; Pershyn, Yuriy P.; Zubarev, Evgeniy N.; Savitskiy, B. A.; Devizenko, I. Y.Документ Nanoscale Co/C multilayer for "carbon window" Schwarzschild objective(STC "Institute for Single Crystals", 2007) Bugayev, Ye. A.; Devizenko, O. Y.; Zubarev, Evgeniy N.; Kondratenko, V. V.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 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.Документ 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.Документ Behavior of the Ti-Zr-Ni thin film containing quasicrystalline and approximant phases under radiative-thermal action in transition modes(Kharkiv Institute of Physics and Technology, 2020) Malykhin, S. V.; Makhlai, V. A.; Surovitskiy, S. V.; Garkusha, I. E.; Herashchenko, S. S.; Kondratenko, V. V.; Kopylets, I. A.; Zubarev, Evgeniy N.; Borisova, S. S.; Fedchenko, A. V.X-ray diffraction and SEM microscopy were used to study the structural and phase changes in a thin film obtained by magnetron sputtering of a Ti52Zr30Ni18 target (at.%) on a steel substrate under the radiation-thermal influence of pulsed hydrogen plasma on an QSPA Kh-50 accelerator. A technique has been worked out for the formation of the quasicrystalline and crystal-approximant phases as a result of high-speed quenching using pulsed action with a heat load of 0.6 MJ/m². The changes in the contents of these phases as well as in their structure and substructure parameters were studied during isothermal vacuum annealing at a temperature of 550 °C and also as a result of irradiation with 5 plasma pulses in the range of heat load from 0.1 to 0.4 MJ/m². The quasicrystalline phase was found to be resistant to irradiation with hydrogen plasma.