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The authors have given results of investigations into the structural and optical properties of InAs nanoclusters formed by the ion-implantation method in silicon and silica matrices. The influence of the heat treatment at a temperature of 900°C and of the irradiation with Xe ions with an energy of 167 MeV and a fluence of 3·1014 cm–2 on the structure and photoluminescence of the formed systems has been found. In the case of the system ″InAs in SiO2″ the irradiation with Xe ions leads to an enhancement of the intensity and a broadening of the luminescence spectrum in the visible spectral region (550–750 nm). The ordering of the nanoclusters and their stretching along the path of the Xe ions in the SiO2 matrix has been found.

A procedure for dispersing multi-walled carbon nanotubes in the two-component polymer SpeciFix-20 (epoxy resin + hardener) using combined hydromechanical and ultrasonic mixing was developed. New composites with carbon nanotubes were produced. Their structures and optical and electrophysical characteristics were studied. The propagation of microwave radiation (26–38 GHz) in experimental composite samples was investigated. It was shown that the strong absorption of the composites appeared only with significant additions of multi-walled carbon nanotubes and was caused by the resulting electrical conductivity of the composites. A size effect of the additive on the optical characteristics of the produced composites was established. Equal absorption coefficients for microwave radiation could be achieved by using a smaller amount of carbon nanotubes with smaller diameters and greater specific surface areas in the composite.

Transmission electron microscopy (TEM), Raman scattering (RS), and photoluminescence (PL) techniques are used to study the structure, phase composition, and radiative properties of silicon with implanted InSb nanocrystals produced by implanting Sb+ and In+ ions with energies of 350 keV and fluences of 3.5·1016 cm–2 followed by heat treatment at 1100°C for 3, 10, and 60 min. The TEM and RS data confirm the formation of InSb nanocrystals with sizes ranging from 2 to 50 nm in the implanted and annealed samples. A broad band in the 0.8–1.05 eV range is detected in low-temperature (4.2 K) PL spectra of the annealed samples. The possible mechanisms for the luminescence in this range are luminescence of InSb nanocrystals and radiative recombination between the conduction band of silicon and an In acceptor.

The radiative properties of non-stoichiometric silicon nitride SiNx fi lms produced by plasma-enhanced chemical vapor deposition were studied. Intense room-temperature photoluminescence (PL) in the visible region was recorded after annealing for both Si-rich (x = 1.13) and N-rich (x = 1.5) silicon nitride fi lms. The position of the PL band maximum depended signifi cantly on the fi lm composition. The PL band maxima for Si-rich and N-rich SiNx fi lms were detected in the red (660 nm) and blue (450 nm) spectral regions, respectively. The effect of the annealing atmosphere on PL of the SiNx fi lms was studied. It was shown that the PL intensity depended not only on the annealing temperature but also on the annealing atmosphere. The observed features of the non-stoichiometric SiNx PL spectra were explained in terms of defect states in the SiNx band gap.

Nanostructured coatings of thickness from 1.5 to 2 μm are applied to Ar+ ions-prepurifi ed stainless steel substrates by means of reactive magnetron sputtering of composite targets with the content of Ti–Zr–Si components 56, 36, 8 at.% and 36, 56, 8 at.%, respectively. Using the methods of Rutherford back scattering and transmission electron microscopy, we studied the structure of the coatings obtained, their phase composition, and the distribution of components over the depth of coatings. The microhardness of coatings was measured and their basic tribomechanical characteristics were investigated. The dependence of the composition and properties of coatings on the conditions of their application has been examined. The optimum regimes of application of coatings with high tribomechanical properties that ensure microhardness of coating of 31 GPa and double decrease in the friction coeffi cient have been determined.

Physicomechanical and electrophysical characteristics of a polyurethane composite doped with carbon-containing materials have been investigated. It has been found that the roughness of the sample’s surface and also the porosity increase with the concentration of the dopant. Volt-ampere characteristics of composite materials point to the activated type of conductivity in these materials; however, at a temperature of nearly 340 K, the type of conductivity is changed. Also, the frequency dependence of the conductivity has been established.

Basic principles of determination of the radiation resistance of structural materials of nuclear reactors with implantation of high-energy hydrogen and helium atoms have been presented. The parameters of the process of implantation of light irons have been calculated. By scanning-electron-microscopy, optical-microscopy, and interference methods, the authors have studied the surface structure of samples of steel-3, stainless steel, and D16 alloy immediately after irradiating them with hydrogen and helium atoms with an energy of 200 to 400 keV in the range of doses from 1016 to 3 · 1017 ions/cm2 and after annealing these samples thermally at temperatures from 300 to 550°C. Threshold blistering doses for all the studied materials and annealing temperatures for visualizing structural defects have been determined.

A study has been made of the physicomechanical and structural properties of polyimide composite films as functions of the concentration of a YBa2Cu3O6+x filler in the range 0.05–0.5 wt.%. A strong influence of the concentration of the filler on the elastic, plastic, and strength properties of the polymer matrix has been shown. A phenomenological model has been proposed that explains the change in the physicomechanical properties of the composite and is based on a four-layer structural scheme.

The optical properties and structure of layers of silicon nitride deposited on silicon substrates by plasma-aided chemical vapor deposition at 300°C are studied by ellipsometry, Raman scattering, IR spectroscopy, and photoluminescence techniques. It is found that immediately after deposition the silicon nitride contains hydrogen in the form of Si-H bonds. Annealing (1100°C, 30 min) leads to dehydrogenation and densification of the nitride layer. An intense Si3N4 photoluminescence signal is detected in the green. Immediately after deposition the photoluminescence peak appears at 542 nm and annealing shifts it to shorter wavelengths.

Polyimide–dispersed YBa2Cu3O6+x composite polymers of various compositions were formed by hot pressing. Changes of Raman spectra were studied as functions of the filler concentration and the γ-irradiation dose.

We studied the effect of ion bombardment on the structure of SOG (spin-on-glass) films. We used IR and Raman spectroscopy and plan-view transmission electron microscopy to study the characteristic features of the structural transformation in organosilicon films when bombarded by nitrogen ions. We show that they are heterogeneous and we establish the presence of inclusions of nanocrystalline graphite.

Superhard nanostructured Ti–Hf–Si–N coatings (films) possessing high physical and mechanical properties have been produced. Nuclear and atomic physical analyses, such as RBS, SIMS, GDMS, SEM-EDXS, XRD, and nanoindentation were used to investigate the elemental and phase composition and the morphology of the films as functions of the pressure in the chamber and of the bias voltage applied to the substrate. It was observed that as the grain size in nc-(Ti, Hf)N coatings was decreased from 6.7 to 5 nm and α-Si3N4 (amorphous or quasi-amorphous phase interlayer between nanograins) formed, the coating nanohardness increased from 42.7 to 48.4 ± 1.6 GPa. However, the further decrease of the (Ti, Hf)N grain size to 4.0 nm resulted in a slight decrease in nanohardness. The stoichiometry of the films changes from (Ti40–Hf9–Si7.5)N46 to (Ti28–Hf18–Si9)N45, and also changed the lattice parameter of the (Ti, Hf)N solid solution. It should be noted that the high-hardness coatings showed the least friction coefficient (0.2), and its value remained unchanged until the coating worn out.

A study has been made of the spectra of electron paramagnetic resonance and of experimental curves of accumulation of free radicals in polytetrafluoroethylene at different temperatures and radiation doses. It has been found that at a temperature of 60°C, the curve of accumulation of stabilized radicals goes through the maximum and thereafter drops exponentially. The change in the parameters of intermolecular interaction causes the transformation of a standardly shaped accumulation curve with saturation to a nonmonotonic curve with a maximum.

A hybrid model, which makes it possible to calculate the influence of the drain voltage and the temperature on the mobility of electrons in the n‐channel of silicon MOS transistors with a high‐alloy substrate in the linear regime of their operation on the basis of a combination of analytical approximations and modeling of electron transfer by the Monte Carlo method, has been proposed.

It is shown theoretically and experimentally that an extended buried homogeneous Si3N4 layer 0.3–0.5 μm thick is formed at certain stages of the self-annealing bombardment of silicon wafers with a high-energy (500 keV per atom) nitrogen molecular-ion beam. The experiments are numerically simulated on the basis of the diffusion equations of chemical kinetics with regard to sputtering, thermal diffusion, and the formation of the nitride phase. The implant localization under the high-temperature (T = 1000°C) annealing of silicon layers irradiated to heavy doses is explained within a fractal model of cluster–cluster aggregation.

Based on results of measurement and processing of volt-ampere characteristics as well as linetic modeling of electron transfer by the Monte Carlo method, the influence of the doping level and the temperature on electron mobility in the n channel of a silicon MOS field-effect transistor operating in a linear regime is investigated.

The process of transport of one-dimensional electrons in a GaAs quantum conductor is investigated by the Monte Carlo method. It is shown that in addition to scattering by polar optical phonons, the heating of charge carriers is also appreciably affected, in the case of electric field intensities higher than 5.105V/m, by ionized-impurity scattering and the transverse dimensions of the conductor.

Multi-energy ion implantation of nitrogen into bulk iron and steel samples with the formation of layers having uniform physical and chemical properties has been investigated. Numerical modeling of the formation of uniformly alloyed layers in a given depth interval have been carried out, taking account of the phenomena of target sputtering and swelling, changes in the stopping properties of the target, radiation-stimulated impurity diffusion, and the formation of new phases.

An analytic expression is obtained for atomic-interaction repulsive potential. The theoretical data agree well with experimental data and quantum-mechanical calculations for small and intermediate interatomic distance and can be used in studying problems on the motion of heavy charged ions in matter.