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NiFe nanocrystalline films were formed onto Au film via pulsed electrolyte deposition with variable time of relaxation between the sequential pulses. Analysis of anomalous non-liner changes in the NiFe film structure showed the implementation of three mechanisms, resulting in "layer-by-layer", "layer-plus-island", or "island" growth. The change of the interpulse relaxation time provides the possibility to realize all three different mechanisms. The grown NiFe films may have different morphology. The ultrathin NiFe films have nanosized grains and exhibit high uniformity of structure, the films may be also combined of less that 10 nm nanoscale grains and their conglomerates, typically, about 50 nm in size, and, additionally, the film structure, consisting of isolated magnetic islands can be realized. The phenomenological explanation of the different mechanisms was obtained using atomic-force-microscopy (AFM) approach. It has been demonstrated that the growth mechanism can be controlled by nanocrystallites conglomeration, which is accelerated with increasing the relaxation time. The origin of the conglomeration process is mainly associated with high surface energy of nanosized grains.

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Microelectronic products are very sensitive to ionizing radiation (electrons, protons, heavy charged particles, X-ray, and γ radiation). Lead is the commonly used material for radiation protection. Bismuth deposition has become an interesting subject for the electrochemical community because of bismuth's unique electrical, physical, and chemical properties. There is a limited number of authors dealing with deposition of continuous bismuth films onto metallic substrates by electrodeposition method. The conditions of Bi electrochemical deposition and the structure of Bi coatings were examined. X-ray diffraction patterns for all samples were indexed to rhombohedral Bi. Coatings with a signified texture (012) are formed in electrolyte without additives. With gelatin the growth texture changes, and the most intense reflex becomes (110). It was found that increasing gelatin concentration from 0.1 to 0.5 g/L leads to Bi microstructural refinement from 4−20 μm, to from 50 nm to 2 μm, respectively. The protection efficiency of Bi-based shields under 1.6−1.8 MeV electron radiation energy was measured. The electron beam attenuation efficiency was estimated by the changing of current−voltage characteristics of semiconductor test structures which were located behind the shields and without them. It has been determined that optimal protection effectiveness and mass-dimensional parameters are enabled by Bi shields with 2 g/cm 2 reduced thickness and 156 attenuation coefficient.

Crystal and magnetic structure of the doped BaFe12-xInxO19 samples were refined by the results of investigations using high resolution neutron powder diffraction and vibration sample magnetometry at different temperatures. The refinements were realized in frame of two space groups. The P63/mmc (No 194) centrosymmetric nonpolar and P63mc (No 186) noncentrosymmetric polar space groups were used. The unit cell parameters, ionic coordinates, thermal isotropic factors, occupation positions, bond lengths and bond angles, microstrain values were established. The magnetic and dipole moments were also defined. It is established that the In3+ cations may be located only in the Fe1 -2a and Fe2 -2b crystallographic positions with equal probability for the sample with lowest substitution level x = 0.1. At the x = 1.2 substitution level about half of the In3+ cations occupies the Fe5 -12k positions. For the last sample the remaining half of the In3+ cations is equiprobably located in the Fe1 -2a and Fe2 -2b positions. The spontaneous polarization was established for these compositions at 300 K. It is studied the influence of the type of substitutive cation and structural parameters on the Fe3+(i) -O2--Fe3+(j) (i, j = 1, 2, 3, 4, 5) indirect superexchange interactions with temperature. With substitution level increase the superexchange interactions between the magnetic positions inside and outside the sublattices are broken which leads to a decrease in the value of their magnetic moments.

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Nanostructured NiFe film was obtained on silicon with a thin gold sublayer via pulsed electrodeposition and annealed at a temperature from 100 to 400 °C in order to study the effect of heat treatment on the surface microstructure and mechanical properties. High-resolution atomic force microscopy made it possible to trace stepwise evolving microstructure under the influence of heat treatment. It was found that NiFe film grains undergo coalescence twice—at ~100 and ~300 °C—in the process of a gradual increase in grain size. The mechanical properties of the Au/NiFe nanostructured system have been investigated by nanoindentation at two various indentation depths, 10 and 50 nm. The results showed the opposite effect of heat treatment on the mechanical properties in the near-surface layer and in the material volume. Surface homogenization in combination with oxidation activation leads to abnormal strengthening and hardening-up of the near-surface layer. At the same time, a nonlinear decrease in hardness and Young’s modulus with increasing temperature of heat treatment characterizes the internal volume of nanostructured NiFe. An explanation of this phenomenon was found in the complex effect of changing the ratio of grain volume/grain boundaries and increasing the concentration of thermally activated diffuse gold atoms from the sublayer to the NiFe film.

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