This paper presents the results of fabricating a model sample of a multilayer coating on a Al2O3 substrate, which consisted of 30 periods of alternately deposited 10.5-nm-thick layers of Ti41Zr41Ni18 and 2.5-nm-thick layers of W. The effect of annealing for 1 h at 500, 600, and 700 °C was studied. Characterization of the phase and structural state of the coating by X-ray diffractometry and small-angle X-ray reflectometry was carried out. It was found that during the annealing process, the tungsten layers in the multilayer composition did not undergo significant changes, and all alterations occur only in the Ti41Zr41Ni18 layers. Annealing affected the thickness of the layers, density, and interlayer roughness. It has been experimentally shown that the phase transformation ”quasicrystal → 2/1 crystalline approximant” is accompanied by an 8.3% volume increase compared to the volume of the quasicrystalline phase, but this does not lead to the destruction of the periodic composition. The multilayer structure proved to be resistant to high temperatures and, despite phase changes, did not lose its bond with the substrate. The used combination of materials and the high annealing temperature did not generate significant internal stresses or mechanical damage. The results obtained in this study allow for the further controlled formation of layered quasicrystal/tungsten microsystems of various designs with different layer thicknesses. The next perspective involves conducting practical tests with plasma to study the radiation-thermal impact.

The temperature dependence of the electrical resistivity in the temperature range from 4.4 to 300 K for Ti41Zr41Ni18 (at. %) thin coatings of different crystal perfection and phase composition was studied. The coatings were deposited by magnetron sputtering with subsequent vacuum annealing in various modes ensuring the formation of several heterophase combinations, which included 1/1 and 2/1 approximation phases, a quasicrystalline icosahedral phase, a Laves phase (Ti, Zr)2Ni, and an α-Ti (Zr) solid solution. The structure before and after annealing was studied by X-ray diffractometry. It was established that coatings with a predominant content of amorphous, quasicrystalline, or approximant 2/1 phases have a temperature coefficient of resistance less than zero, while samples with a predominance of crystalline phases demonstrate characteristic metallic conductivity. The temperature dependence of the electrical resistivity of the Ti41Zr41Ni18 quasicrystalline coating turned out to be similar to the dependence in bulk samples of the Ti40Zr40Ni20 composition. The electrical resistivity of the approximant 2/1 phase with a low content of the additional Laves phase in the film has an almost constant value in the entire investigated temperature range.

Исследован механизм взрывной кристаллизации аморфных плёнок кобальта, выращенных на аморфном углероде в отсутствии и при наличии сильного неоднородного магнитного поля.Установлено, что ключевым фактором для реализации взрывной кристаллизации является углерод, поступающий в плёнку кобальта из работающего С-магнетрона во время осаждения слоя кобальта.Легирование растущей плёнки кобальта

Results of study of formation and structure-transformation features of magnetron deposited W5Si3/Si multilayer coating are presented. The W5Si3/Si multilayer is chosen to create multilayer Laue lens designed for focusing x-rays with energy E > 10 keV. As shown, the multilayer-coating synthesis is accompanied by compression-stress formation. Stress reduction is proposed and optimal annealing temperature is found out. As revealed, annealing with a temperature above 400 degrees C is accompanied by interaction between the layers, thickness ratio changing, and period decrease. Growth of intermixing layers with composition close to WSi2 after annealing with temperature above 400 degrees C is assumed. As shown, the WSi2, crystallization begins at 600 degrees C, and the coating peeling starts at 650 degrees C.

The high transparency of carbon-containing materials in the spectral region of "carbon window" (lambda approximately 4.5-5nm) introduces new opportunities for various soft X-ray microscopy applications. The development of efficient multilayer coated X-ray optics operating at the wavelengths of about 4.5nm has stimulated a series of our imaging experiments to study thick biological and synthetic objects. Our experimental set-up consisted of a laser plasma X-ray source generated with the 2nd harmonics of Nd-glass laser, scandium-based thin-film filters, Co/C multilayer mirror and X-ray film UF-4. All soft X-ray images were produced with a single nanosecond exposure and demonstrated appropriate absorption contrast and detector-limited spatial resolution. A special attention was paid to the 3D imaging of thick low-density foam materials to be used in design of laser fusion targets.

The thermal-induced structural and phase transformations in dc-magnetron deposited Co/C multilayered periodical compositions (MPC) are studied by transmission electron microscopy, x-ray phase analysis, and small angle x-ray diffractometry. High level of periodicity is observed in Co/C MPC with Co thickness 2 nm at temperatures below 300 degrees C and in MPC with Co thickness 7 nm at temperatures below 400 degrees C. This thermal range can be used to control period increase. As shown, 2 nm-thick amorphous cobalt layers at T >= 330 degrees C are crystallized in f.c.c. phase with agglomeration of Co layers. As revealed, the agglomeration of 7 nm-thick Co layer begins after heating above 400 degrees C. Transition of h.c.p. Co to f.c.c. Co takes place after annealing above 500 degrees C. Agglomeration of Co layers proceeds in similar manner in both MPC, and mechanism of MPC damage is independent on initial structural state of Co layers. Textured graphite layers with (0002) planes parallel to the film surface occupy the space vacated during Co agglomeration.

The interlayer interaction features of the d.c.-magnetron deposited nanolayers in periodical Co/C multilayers and the C/Co/C three-layers are studied by small-angle x-ray diffraction and transmission electron microscopy. As revealed, there is an interaction between adjacent layers of coatings, and an amount of carbon taking part in interaction with Co is changing with a non-monotonic function versus cobalt thickness. As shown, the amorphous cobalt-containing layers are crystallized into f.c.c. Co when their thickness exceeds 5 or 10 nm for Co/C multilayers or C/Co/C three-layer coatings, respectively. The cobalt layers have a perfect-enough crystal [0001] texture in three-layers.