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The article presents the results of studies of elastomers modified by multilayer carbon nanotubes (MCNTs). An elastomer, polydimethylsiloxane, served as the polymer base while MCNTs synthesized on Co–Mo/Al2O3–MgO and Fe–Co/2.1Al2O3 catalysts were used as a filler. The structural analysis of particle sizes of MCNTs was carried out. It showed that MCNTs synthesized on Co–Mo/Al2O3–MgO catalysts have the outer diameter of 25–35 nm and the inner diameter of 10–15 nm, while MCNTs synthesized on Fe–Co/2.1Al2O3 catalysts have the outer diameter of 5–15 nm and the inner diameter of 5–7 nm. The electrical conductivity of the heating elements samples was studied. The maximum electrical conductivity (1.66×10–1 Sm/cm) was observed for a composite based on polydimethylsiloxane modified with 7 wt % MCNTs (synthesized on the Co–Mo/Al2O3–MgO catalyst) while the sample modified with MCNTs (synthesized on the Fe–Co/2.1Al2O3 catalyst) had the maximum heat release rate coupled with evenly distributed heat flow pattern. The maximum heating temperature of 102°C corresponded to a constant voltage of 18–24 V. The studies of electromagnetic radiation interaction with the samples were executed. In those studies, heating element samples made of MCNTs (synthesized on the Fe–Co/2.1Al2O3 catalyst) demonstrated wide-band attenuation of impinging radiation (up to 20%) while heating element samples made of MCNTs (synthesized on the Co–Mo/Al2O3–MgO catalyst) showed the ability of electromagnetic shielding in the range of 26 to 40 GHz at the level of 15%.

This work presents a study of the conditions and possibilities for the intercalation of hexafluorophosphate anions into CNT-based electrodes. For this, cathodes based on CNTs synthesized on different catalysts (Co–Mo)/(Al2O3–MgO) and (Fe–Co)/2.1Al2O3 were produced. As a result, electrode materials were obtained at various concentrations of CNT/graphite: CNT-4F, CNT-6, and CNT-6F. The resulting electrodes were studied by cyclic voltammetry (CVA) in an electrolyte of a dissolved LiPF 6 salt based on EC : DEC (ethylene carbonate : diethylene carbonate) solvents (in the ratio 1 : 1 : 1) with an admixture of 3% VC at a sweep speed of 4 mV/s. On the basis of the obtained CVA dependences, the specific charge/discharge capacity of the electrodes CNT-4F, CNT-6, and CNT-6F was determined. The largest specific charge/discharge capacity calculated per mass of CNTs was 292 and 164.22 (mA h)/g for CNT-4/graphite electrodes, and the minimum specific charge/discharge capacity was 41.67 and 1.5 (mA h)/g for CNT-4 electrodes without graphite, respectively. Also, the dependences of the average electrode utilization coefficient on the charge time at constant current on the cycle number at a charge of 300 s were obtained. For chronoamperograms of individual steps of the СNT-6F electrode, the values of lithium diffusion coefficients were calculated.

SiO2 /Si, SiN1.2/SiO2 /Si and SiO2 /SiN0.9/SiO2 /Si structures have been fabricated by chemical vapor deposition and thermal oxidation of silicon. The elemental composition and thicknesses of dielectric layers have been studied using Rutherford backscattering spectroscopy, scanning electron microscopy, and spectral ellipsometry. The electroluminescence (EL) of the samples has been investigated in the “electrolyte–dielectric–semiconductor” system at a positive bias voltage applied to the silicon substrate. An intense band with maxima at 1.9 eV appears on the EL spectra of the SiO2 /Si sample, while the EL spectra of the SiN1.2/SiO2 /Si and SiO2 /SiN0.9/SiO2 /Si samples are characterized by the presence of bands with the maximum values of 1.9, 2.3 and 2.7 eV. The nature of these bands is discussed. Passing a charge in the range of 100–500 mC/ cm2 through the SiO2 /SiN0.9/SiO2 /Si sample, an increase in the EL intensity was recorded in the entire visible range. Passing a charge of 1 C/cm2 through a sample with a three-layer dielectric film resulted in the EL intensity decrease. It can be explained by the upper oxide layer degradation. It has been shown that silicon nitride deposited on top of the SiO2 layer protects the oxide layer from field degradation and premature breakdown. The most stable electroluminescence when exposed to a strong electric field is observed for the structure SiN1.2/SiO2 /Si.

The electrophysical properties and the resistive switching effect in ITO/SiNx/Si memristor structures have been investigated. A silicon nitride film ~200 nm thick with a Si/N ratio varying with depth has been deposited on a silicon substrate by chemical vapor deposition. The current–voltage characteristics of ITO/SiNx/Si-p structures have shown that the conduction mechanism in a high-resistivity state depends on the properties of the nitride film and is described in terms of the Pool–Frenkel model, which takes into consideration electron hops between neighboring traps. When the polarity of the voltage applied to the structure changes sign, conducting channels in the nitride film break down and the structure switches over to a high-resistivity state. The photoswitching effect has been discovered in the ITO/SiNx/Si structure, which opens up a new frontier for using memristors in silicon optoelectronic devices.

The heat effects at flow of direct current in nanomodified elastomers of two types (polyurethane and silicone compounds) were investigated. The multiwalled carbon nanotubes (MWCNT) synthesized over the (Co–Mo)/(Al2O3–MgO) and (Fe–Co)/2.1Al2O3 catalysts were used for nanomodification. The particle size analysis of MWCNT was carried out because the MWCNTs with various morphological parameters were synthesized over this type of catalysts. The composite manufactured on the basis of a silicone compound modified by 7 wt % of MWCNTs synthesized over the (Co–Mo)/(Al2O3–MgO) catalyst has the highest electrical conductivity (1.66 × 10–1 S cm–1), and the composite manufactured from the polyurethane compound modified by 1 wt % of MWCNT synthesized over the (Fe–Co)/2.1Al2O3 catalyst has the lowest electrical conductivity (6 × 10–10 S cm–1). Variations in heat dissipations for various types of elastomers modified by MWCNT were detected by using the noncontact method of measuring of temperature field on the surface of samples. The manner of stabilized heat dissipation which is natural for the materials with a positive temperature coefficient of resistance was found. The highest intensity of heat dissipations combined with uniform distribution of the temperature field was observed for the samples manufactured on the basis of a silicone compound containing 7 wt % of the MWCNTs synthesized over the (Fe–Co)/2.1Al2O3 catalyst. The maximum heating temperature for the sample operating under the voltage of 6 V of direct current was 102°C. Nonuniformity of heat dissipations is specific to almost all samples manufactured on the basis of the polyurethane compound. In this case, the samples based on the silicone compound demonstrate uniform heating at any level of filling by the MWCNTs. As a part of the study, a honey-combed sample was obtained, which, under the voltage of 6 V of direct current, was heated to 100°C and had a uniform distribution of the temperature field.

The paper presents results of studies of the optical and electromagnetic properties of the WO3/rGO electrochromic nanocomposite films obtained by mechanical spraying of a water-based dispersed solution with WO3/GO particles and heat treatment (annealing) at a temperature of 300°C in an inert argon atmosphere for 24 hours. As a result, an electrically conductive phase of reduced graphene oxide rGO and crystalline WO3 were formed.

The paper is dedicated to investigation of the influence of rapid thermal treatment on the microstructure of platinum silicide. The Pt films 43.7 nm thick were applied on the substrates of the monocrystal silicon by means of the magnetronic sputtering of platinum with the purity of 99.95 % on the МРС 603 set-up with the cryogenic pumping to the pressure not worse than 5*10-5 Pa. As an operating medium, argon was used with the purity of 99.933 %. Rapid thermal treatment of samples was performed in the thermal balance conditions by irradiating the non-working side of the wafer with the incoherent light flow in the nitrogen atmosphere during 7 s at the temperatures of 200-550 °C. The irradiation source in the set-up was represented by the quartz halogen incandescent lamps. The comparative analysis was done through the traditional long thermal treatment of the platinum films at a temperature of 550 о С for 30 min in the nitrogen atmosphere. Investigations of the platinum silicide microstructure were performed by means of the transmission electron microscopy which demonstrated that the increase in the RTT temperature initiates first the annealing of defects on the inter-grain boundaries, which is evident from the more distinct contrast from the grains, and then one can observe their growth reflecting the forming of the new phase (silicide one). Such progress of changes of the platinum silicide microstructure and of the size of the grains with the increase in treatment temperature is determined by the heat of its forming. As the Pt2Si phase forming heat is minimum and constitutes 10.4-16.8 Kkal/atom of metal, and for PtSi - 15.7-25.5 Kkal/atom of metal, then the forming of a stable PtSi structure requires a higher temperature. The authors carried out calculations of the activation energy of the diffusion synthesis of platinum silicide during rapid thermal treatment. The calculations show that it is 0.37 eV smaller, than during the long thermal treatment. This means that in this case this process is subject to acceleration related to the rupture of the silicon-silicon bonds and electron excitation in silicon under the influence of the photon flow.

The paper is purposed to establish the principles of the micro-structural changes of Pt-Si system during the rapid thermal treatment. The Pt films 43.7 nm thick were applied on the substrates of mono-crystal silicon KEF 0.5 with orientation (111) by means of the magnetron platinum target sputtering (purity of 99.95 %) on the unit MPC 603 with the cryogen pumping to the pressure of no less than 5∙10-5 Pa. Argon was used as a working medium, whose purity constituted 99.933 %. Rapid thermal treatment was performed in the mode of the thermal balance with irradiation of the reverse side of the wafer by means of the non-coherent light flow in the nitrogen medium within the temperature range from 200 to 550 °C with a step of 50 °С during 7 s. In parallel, the solid phase synthesis was performed of platinum silicide by means of the standard method with application of the continuous single stage thermal treatment in the analogue medium (T = 550 °C, t = 30 min). Temperature monitoring was performed by means of the thermal couple method with accuracy of ±0.5 °C. The grain size was determined by the translucent electron microscopy method. Thickness of platinum silicide under formation, its surface micro-relief and the separation boundaries with silicon were determined by means of the raster electron microscopy. It is demonstrated, that with the rise of the rapid thermal treatment one can observe growth of the platinum film on silicon. A comparative analysis was conducted of the average size of grains, micro-relief of the PtSi surface and its separation boundary with silicon for two methods of its formation with application of the rapid thermal treatment and with application of the traditional continuous thermal treatment at the temperature of 550 °C during 30 min in the nitrogen atmosphere. By means of the raster electron microscopy method it is demonstrated, that size of the micro-relief on the separation boundary of PtSi-Si does not exceed 15.9 nm and the size of grains is 37.7 nm. This is in 2.5 and 3.1 times smaller, then in the case of the traditional single stage continuous thermal treatment.

The light-emitting properties of Si-rich silicon nitride films deposited on the Si (100) substrate by plasma-enhanced (PECVD) and low-pressure chemical vapor deposition (LPCVD) have been investigated. In spite of the similar stoichiometry (SiN1.1), nitride films fabricated by different techniques emit in different spectral ranges. Photoluminescence (PL) maxima lay in red (640 nm) and blue (470 nm) spectral range for the PECVD and LPCVD SiN1.1 films, respectively. It has been shown that equilibrium furnace annealing and laser annealing by ruby laser (694 nm, 70 ns) affect PL spectra of PECVD and LPCVD SiN1.1 in a different way. Furnace annealing at 600 °C results in a significant increase of the PL intensity of the PECVD film, while annealing of LPCVD films result only in PL quenching. It has been concluded that laser annealing is not appropriate for the PECVD film. The dominated red band in the PL spectrum of the PECVD film monotonically decreases with increasing an energy density of laser pulses from 0.45 to 1.4 J/cm2. Besides, the ablation of PECVD nitride films is observed after irradiation by laser pulses with an energy density of > 1 J/cm2. This effect is accompanied by an increase in blue emission attributed to the formation of a polysilicon layer under the nitride film. In contrast, the LPCVD film demonstrates the high stability to pulsed laser exposure. Besides, an increase in the PL intensity for LPCVD films is observed after irradiation by a double laser pulse (1.4 + 2 J/cm2) which has not been achieved by furnace annealing.

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.

ZnSe nanocrystals have been formed in the silicon dioxide matrix by the sequential high-fluence implantation of Zn + and Se + ions at 500 °C. After implantation a part of samples was annealed at 1000 °C for 3 min using rapid thermal annealing. Structural and optical properties of ZnSe/SiO 2 nano-composite films were analyzed by means of Rutherford Backscattering Spectrometry, cross-sectional Transmission Electron Microscopy, Raman scattering and photoluminescence techniques. It was shown that a sequence of implantation affects structural and optical properties of synthesized ZnSe clusters. Based on the Raman scattering and photoluminescence data the samples for which Zn ions were implanted first exhibited a better ZnSe crystalline quality than those of reverse sequence of implantation, i.e. with Se ions implanted at the beginning. The bands of blue ZnSe band edge emission and green-red ZnSe deep defect level emission were revealed in the PL spectra of the as-implanted and annealed nano-composites. The PL spectral features observed in the blue region are due to the quantum-size effects in the ZnSe nanocrystals embedded into the silicon dioxide matrix. The PL intensity ratio of the deep defect band to the near edge emission is higher in the samples first implanted with Se ions, and Zn ions implanted next. The effect of rapid thermal annealing on structural and light-emitting properties was discussed.

Till now, shape elongation phenomenon was observed predominantly for metal nanoparticles irradiated with swift heavy ions (SHI). For the first time, we report the shape elongation of InAs and Zn(core)/ZnO(shell) nanoparticles (NPs) embedded in a silica matrix and irradiated with swift Xe ions. In case of InAs NPs, SHI irradiation results in the formation of nanorods. A diversity of elongated features is observed for Zn-based NPs: chains of small ZnO clusters, elongated (Zn)core/(ZnO)shell structures and drop-like elongated Zn particles. The intense sputtering of the silicon dioxide layer due to electronic excitations has revealed for “SiO2+Zn-based NPs” composite. Photoluminescence (PL) spectroscopy reveals emission in the visible range for two types of nanocomposites before SHIs irradiation. This emission is attributed to the oxygen excess-related defect (NBOHC) as well as to the oxygen deficiency-related centres created in silica matrix during the implantation of cluster-forming ions (In + As or Zn). The intensive band in the spectral region of 2.8 – 3.1 eV is observed in PL spectrum of annealed “SiO2+InAs NPs” composite. SHI irradiation results in its quenching and formation of an asymmetrical band centred at 1.9 eV. In case of “SiO2+Zn-based NPs” composite, SHIs irradiation results in substantial increase of PL in orange spectral range. The origin of observed emission is discussed.

The results of studies of the structure, stress, and hardness of Ti–N, Cr–N and Ti–Cr–N coatings deposited by the PIII&D method using the rectilinear vacuum-arc plasma filter are presented. X-ray structural analysis was used to study the effect of the pulse bias potential amplitude in the range from 0.5 to 1.5 kV on the characteristics of the coatings. In accordance with the composition of the cathode, the coatings have the nanocrystalline cubic structure TiN, CrN or solid solution (Ti, Cr)N (structural type NaCl) with axial texture [110]. The content of Cr in (Ti, Cr)N coatings is 1.5 times higher than in the cathode. It was found that the change of the pulse bias potential amplitude practically does not affect the elemental composition of the coatings. The level of compression stress and the size of crystallites in (Ti, Cr)N coatings are less than in TiN coatings obtained under similar conditions. All TiN and (Ti, Cr)N coatings have a high hardness of 29–36 GPa.

In the present work, silicon nitride, and oxide films, as well as two-layered SiNx/SiO2 and three-layered SiO2/SiNx/SiO2 structures, were fabricated on p-type Si-substrates. The structure and element composition was studied by scanning electron microscopy and Rutherford backscattering spectroscopy, respectively. It was shown, spectral positions of photoluminescence maxima, as well as edge absorption, were determined by stoichiometry of SiNx layers. No electroluminescence signal was registered from single-layered silicon nitride films. The intense band at 1.9 eV dominated the electroluminescence spectra of single-layered silica film as well as two- and three-layered structures. It was attributed to silane groups in SiO2 layers. The contribution of emission from silicon nitride layers into electroluminescence of the two- and three-layered structures is discussed.

The process of irradiation of metals with ions is an effective method for changing various properties of materials, in particular titanium, as well as obtaining new materials. This work is devoted to modeling radiation processes in titanium irradiated with ions. Algorithms of cascade-probabilistic functions CPF) computation depending on the number of interactions and the particle penetration deep number for various incident particles of the Mendeleev's periodic table in titanium are presented. Approximate value expressions for cross-sections are chosen, patterns of cooperation cross-sections demeanor, CP-functions depending on observation profound, number of interactions, target atomic number, primary particle initial energy are noted. Algorithms for calculating the radiation imperfections concentration in ion radiation have been developed and computations in titanium in ion radiation have been carried out. With the calculating CPF and the depth distribution of vacancy clusters, it is necessary to find the region of the result in which these characteristics of the process of formation of radiation defects in solids are exists. Regularities obtained when finding this area are formulated. The calculation results in the form of graphs and tables are presented. Keywords: Modeling, algorithm, computation, ion, regularities, approximate value, CPF, cooperation cross-section, concentration, vacancy accumulations.

The two triple-layered SiO 2 /SiN x /SiO 2 structures with Si-rich and N-rich silicon nitride active layer were fabricated on p -type Si-substrates by chemical vapour deposition. The SiN x layer of different composition ( x = 0.9 and x = 1.4) was obtained by changing the ratio of the SiH 2 Cl 2 /NH 3 flow rates during deposition of a silicon nitride active layer (8/1 and 1/8, respectively). The spectroscopic ellipsometry and photoluminescence (PL) measurements showed that the refractive index, the absorbance and luminescence properties depend on a chemical composition of silicon nitride layers. The structures with Si-rich and N-rich SiN x active layers emit in the red (1.9 eV) and blue (2.6 eV) spectral ranges, respectively. The PL intensities of different structures are comparable. The rapid thermal annealing results in the intensity decrease and in the PL spectra narrowing in the case of SiN 1,4 active layer, whereas the increase in the emission intensity and the PL spectra broadening are observed in the case of the annealed sample with a SiN 0,9 active layer. The PL origin and the effect of annealing treatment have been discussed, taking into account the band tail mechanism of radiative recombination. Multilayered (SiO 2 /SiN x ) n /Si structures are of practical interest for creation of effective light sources on the basis of current Si technology.

Oxide-nitride-oxide-silicon (SiO2/SiN0.9/SiO2/Si) structures have been fabricated by chemical vapor deposition. The elemental composition and light emission properties of “SiO2/SiN0.9/SiO2/Si” structures have been studied using Rutherford backscattering spectroscopy (RBS), photo- and electroluminescence (Pl, El). The RBS measurements has shown the presence of an intermediate silicon oxynitride layers at the SiO2–SiN0.9 interfaces.It has been shown that the photoluminescence of the SiO2/SiN0.9/SiO2/Si structure is due to the emission of a SiN0.9 layer, and the electroluminescence is attributed to the emission of silicon oxide and oxynitride layers. A broad intense band with a maximum at 1.9 eV dominates the Pl spectrum. This band attributed to the radiative recombination of excited carriers between the band tail states of the SiN0.9 layer. The origin of the less intense Pl band at 2.8 eV is associated with the presence of nitrogen defects in the silicon nitride.El was excited in the electrolyte-dielectric-semiconductor system. The electric field strength in the SiO2 layers reached 7–8 MV/cm and exceeded this parameter in nitride layer nearly four times. The electrons accelerating in electric field of 7–8 MV/cm could heat up to energies more than 5 eV. It is sufficient for the excitation of luminescence centres in the silicon oxide and oxynitride layers. The SiO2/SiN0.9/SiO2/Si composition El bands with quantum energies of 1.9 and 2.3 eV are related to the presence of silanol groups (Si–OH) and three-coordinated silicon atoms (≡Si•) in the silicon oxide layers. The El band with an energy of 2.7 eV is attributed to the radiative relaxation of silylene (O2=Si:) centers in the silicon oxynitride regions. It is observed the least reduction of this band intensity under the influence of strong electric fields after a charge flow of 1–3 C/cm2.

Ti–Al–C–N coatings were produced by reactive magnetron deposition at different substrate temperatures Ts (220, 340 and 440 °C) and bias voltages Ubias (–90, –150 and –200 V). Using the energy dispersive X-ray spectroscopy method, it was found that the increase of the bias voltage led to a growth of argon atomic concentration and the (Al + Ti) / (Ti + N) ratio and to a decrease of the trace oxygen concentration in Ti–Al–C–N coatings. The growth of Ts promoted a decrease in the oxygen concentration. By means of scanning electron microscopy, a change in the type of the microstructure (columnar, granular and mixed columnar-granular) of coatings by varying Ts and Ubias was found. Electrophysical measurements showed the change of the film resistivity (1982–3169 μΩ · cm) when the deposition conditions were varied. The solar absorptance αs was varied from 0.24 to 0.54, the emittance ε was varied from 0.33 to 0.52, and the αs / ε ratio was varied from 0.60 to 1.44 by changing Ts and Ubias. The obtained results indicate the opportunity to vary the Ti–Al–C–N films electrophysical and optical characteristics by choosing optimal substrate heating temperature and bias voltage.

ZnSe nanocrystals have been formed in the silicon dioxide matrix by the sequential high-fluence implantation of Zn+ and Se+ ions at 500 °C. After implantation a part of samples was annealed at 1000 °C for 3 min using rapid thermal annealing. Structural and optical properties of ZnSe/SiO2 nano-composite films were analyzed by means of Rutherford Backscattering Spectrometry, cross-sectional Transmission Electron Microscopy, Raman scattering and photoluminescence techniques. It was shown that a sequence of implantation affects structural and optical properties of synthesized ZnSe clusters. Based on the Raman scattering and photoluminescence data the samples for which Zn ions were implanted first exhibited a better ZnSe crystalline quality than those of reverse sequence of implantation, i.e. with Se ions implanted at the beginning. The bands of blue ZnSe band edge emission and green-red ZnSe deep defect level emission were revealed in the PL spectra of the as-implanted and annealed nano-composites. The PL spectral features observed in the blue region are due to the quantum-size effects in the ZnSe nanocrystals embedded into the silicon dioxide matrix. The PL intensity ratio of the deep defect band to the near edge emission is higher in the samples first implanted with Se ions, and Zn ions implanted next. The effect of rapid thermal annealing on structural and light-emitting properties was discussed.

The paper shows the advantage of silicon nitride for use as a light-emitting element in integrated circuits. Alongwith this, the chosen methods for obtaining the studied samples enable us to determine all possible causesresponsible for radiative recombination. The effect of irradiation with Xe+ ions of 200 MeV in the dose range109 – 1014 ions/cm2 on the optical properties and the structure of silicon enriched silicon nitride (SRN) filmsdeposited on the Si substrate by chemical vapor deposition under low pressure was studied. Based on the Ramanscattering (RS) data, it was concluded that the irradiation by 200 MeV Xe ions with a dose of 1×1014 ions/cm2leads to the dissolution of the amorphous Si phase in the nitride matrix. According to the results of transmissionelectron microscopy, preliminary irradiation with swift heavy ions (SHI) enhances the phase separation processin the nitride layer with a 22% excess of Si during the subsequent annealing at 1100°C for 60 minutes. The SHIirradiation, followed by the heat treatment, leads to a further increase in the intensity of the photoluminescence(PL) in the spectral range 600–750 nm compared with that in case of annealed films without preliminaryirradiation. It is known that radiation in this spectral range is due to Si nanocrystals (Si NCs).

It has been found that “hot” high-fluence Zn+ implantation leads to the formation of the extended layer with zinc-based nanoclusters of size up to 10 nm in SiO2 film. The precipitate’s crystalline nature is confirmed by HRTEM studies. Post-implantation annealing at 700°C for 60 min leads to Zn atoms redistribution in implanted region, formation of the larger crystallites (up to 25 nm) and the small Zn nanoparticles surrounded by the oxide shells (core (Zn)/shell(ZnO) structure) as well as the voids formation at the interface “Zn nanocluster/SiO2 matrix”. The number of the core (Zn)/shell (ZnO) structures and the voids increases after annealing at 700°C for 120 min.

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.

Si-rich (SiN 1.1 ) and N-rich (SiN 1.5 ) silicon nitride films were grown on the Si wafers by plasma-enhanced chemical vapor deposition. Their composition and structure were investigated by Rutherford backscattering spectroscopy and transmission electron microscopy. The effect of composition and post-deposition annealing temperature on the SiN x light-emitting properties was investigated by the examination of photoluminescence. The intensive bands for the Si-rich and N-rich nitride films were detected in the red and blue spectral ranges, respectively. Photoluminescence bands transformations for the annealed nitride films can be ascribed to the increasing K- and N-centre concentration via the Si H and N H bonds rupture and the competitive processes of defect annihilation. On the basis of photoluminescence band FWHM broadening with “ x ” increasing, the FWHM dependence on the measurement temperature and SiN x films inhomogeneous structure, the emission from the SiN 1.1 and SiN 1.5 films is attributed to the transitions between the bands of defect and tail states associated with chemical disordering.

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.

ZnSe nanocrystals have been synthesized in the silicon dioxide matrix by ion implantation of Zn+ and Se+ ions at 25 and 550 °C with subsequent rapid thermal annealing at 1000 °C for 3 min. Structural and optical properties of implanted films were analyzed using Rutherford backscattering spectrometry, transmission electron microscopy, Raman spectroscopy, and photoluminescence. It was shown that the temperature of implantation, as well as thermal treatment, affects the structural and optical properties of implanted films. In the case of high-temperature implantation, ZnSe nanocrystals have been formed already during the implantation process. In the case of room-temperature implanted samples, ZnSe nanocrystals have been synthesized only after subsequent rapid thermal annealing. It was found that implanted silica layers exhibit photoluminescence in wide visible spectral range. The origin of photoluminescence of the as-implanted and annealed silica samples is discussed.

On the surfaces of crystalline semi-insulating GaAs (100), irradiated with noble gas Ar + and Xe + layers of native oxides are formed in the air under ordinary conditions. The surface atomic density of elements and chemical composition of those near the surface layers were studied by means of Rutherford backscattering spectroscopy, nuclear reaction and X-ray photoelectron spectroscopy. In these layers the dependences of the surface atomic density of oxygen and chemical compositions as a function of doses in the region from 1 × 10 13 to 1 × 10 16 ions/cm 2 were determined. It was found that the former value depends on the kind of implanted ions and the relationships of Ga 2 O 3 , As 2 O 3 and As 2 O 5 in the native oxide layers changed with the increase of the fluence. Moreover, the concentrations of Ga 2 O 3 increased and those of As 2 O 3 and As 2 O 5 decreased with the increasing irradiation fluence.

The latent track formation in silicon dioxide (SiO 2 ) and silicon nitride (Si 3 N 4 ) irradiated with swift heavy ions (SHI) has been studied using computer simulation in the frame of the thermal spike model. We have calculated radii and lifetime of the molten regions, or the regions heated to the melting point, formed in SiO 2 and Si 3 N 4 along the ion trajectories for F, S, Cl, Ar, Kr and Xe ions in an energy range of (28–200) MeV. The radius of the molten region was chosen as a criterion for track “etchability” in the case of SiO 2 . The results of computer simulation have been compared with the experimental results of track etching in 4% aqueous solution of hydrofluoric acid (HF). The validity of the criterion taken for the creation of homogeneous “etchable” ion tracks in SiO 2 , namely, the formation of a molten region with radius larger than 3.0 nm [1] in the matrix along the ion trajectory, has been confirmed. It has been found that both the etched track depth and diameter increase with the fluence for the same type of ion species. Under our experimental conditions, for the case of Si 3 N 4 we failed to etch regular conical channels with uniform size distribution .

The radiation resistance of nanostructured TiN, TiAlN, and TiAlYN coatings is studied after 500-keV He+ ion irradiation in the fluence range 5 × 1016–3 × 1017 ions/cm2. The radiation-induced changes in the phase composition, the structure, the lattice parameters, the morphology, and the mechanical properties of coatings are investigated. Blistering is found to be absent, and the radiation fluence is shown to affect the strength properties of the thin coatings nonlinearly. A significant decrease in the grain sizes is detected upon ion irradiation, which causes an increase in the microhardness and the radiation resistance of the coatings. The TiN, TiAlN, and TiAlYN coatings are found to be radiation-resistant coatings, which do not undergo serious degradation during high-fluence ion irradiation.

The process of latent track etching in SiO2/Si structures irradiated with 40Ar (38 MeV), 84Kr (59 MeV) and 132Xe (133 and 200 MeV) ions has been investigated. The experimental results of SiO2 etching in a hydrofluoric acid solution have been compared with the results of computer simulation based on the thermal spike model. It has been confirmed that the formation of a molten region along the swift ion trajectory with minimum radius of 3 nm can serve as a theoretical criterion for the reproducible latent track etching tracks in SiO2.

The effect of pre-hardening of steel substrate on mechanical and tribological properties of TiN and TiAlN coating–steel substrate composites was studied for various treatment conditions. We have found that prior nitrocarburization of the steel substrate increases the microhardness by 7 times, the wear resistance of the working surface of the composite up to 2.3 times, the resilience of the composite by 4.5 times. It is thus feasible to produce thinner coatings in composite layered systems with no drawbacks regarding performance. We also suggest a method to determine wear resistance of the deposited coatings, as well as to estimate the influence of the hardness gradient and contribution of all layers to overall durability of such layered systems.

The implantation formation of InAs nanoclusters in silicon and silica and their modification via irradiation with Xe ions with an energy of 167 MeV and a fluence of 3 × 1014 cm–2 are studied. It is found that post-implantation annealing and irradiation with high-energy ions alter the size and shape of nanoclusters and cause structural transformations within them. The ordering of nanoclusters and their elongation along the trajectory of Xe ions in a SiO2 matrix is observed.

Structural and absorption properties of Te-implanted silicon layers after pulsed laser melting, equilibrium furnace annealing and rapid thermal annealing were examined and compared. The advantage of laser annealing in the formation of absorbing silicon-based layers is demonstrated. Silicon layers doped with Te up to concentrations of (3–5) × 1020 cm−3 were formed via ion implantation and pulsed laser melting. It is found that 70–90% of the embedded impurity atoms are in substitutional states in the silicon lattice. A significant increase of the absorption (to 35–65%) in the wavelength range of 1100–2500 nm is obtained, which is useful for Si-based photodiodes. The effect of energy density of the laser pulse on the structural and optical properties of Te-hyperdoped silicon is discussed. The current-voltage characteristics and the photosensitivity of Te-doped silicon photodiodes are investigated.

The growth of GaN nanocrystals in an amorphous SiO2 matrix by sequential Ga and N implantation and rapid thermal annealing is reported. The effect of the implantation and annealing conditions on the distribution of the implanted ions, as well as the size, static disorder, and stability of the grown GaN nanocrystals, is studied by means of transmission electron microscopy, Rutherford backscattering spectrometry, Raman scattering, and extended X-ray absorption fine structure spectroscopies. It is found that the optimum temperature range for the post-implantation annealing of the nanocrystals, with a size that ranges from about 3 to 12 nm, is 1000–1100 °C. Higher temperatures result in the dissociation of the nanocrystals and out-diffusion of N and Ga, whereas lower temperatures are insufficient for the growth of GaN nanocrystals. Annealing for 30–90 s is optimum in order to avoid considerable loss of N and Ga. However, upon annealing at higher temperatures within the optimum range, up to 1100 °C, or for longer times, up to 120 s, larger GaN nanocrystals are grown and/or lower static disorder is observed.

Selenium hyperdoped silicon is a promising material for intermediate-band solar cells and extended infrared photodiodes. Selenium-rich layers were fabricated by Se ion implantation followed by pulsed laser annealing (690 nm, 70 ns). Laser energy density W was set as 1.5, 2 and 2.5 J/cm2 and number of impulses was set as 1 or 3 for each energy density. Rutherford backscattering with channeling, Raman scattering, scanning electron and optical microscopy as well as photoluminescence techniques were used for diagnostics of structural and optical properties of Se-rich silicon layers. It has been shown that laser irradiation leads to silicon recrystallization and significant impurity redistribution in the implanted layer. It has been observed the formation of the uniform plateau with a concentration of Se around $(3\times 10^{19}-4\times 10^{20})\mathrm{cm}^{-3}$ up to a depth of 300–400 nm with an accumulation of impurity in a near-surface oxide layer 5–10 nm. According to the RBS/channeling data, the substitutional fraction of incorporated Se atoms in silicon lattice after laser treatment is 60-80%. Analysis of photoluminescence spectra has revealed that pulsed laser irradiation of the implanted layer with $\mathrm{W} = 1.5\mathrm{J}/\mathrm{cm}^{2}$ leads to the formation of vacancy and interstitial clusters. As the energy in the pulse increases, the bands related with these types of defects disappear from the photoluminescence spectra.

We have studied structural transformations in pre-damaged GaAs crystals irradiated with high-energy Bi ions (710 MeV, 4.3 × 1012 cm−2). The pre-damage has been created via irradiation with swift electrons (4 MeV, 4 × 1017 cm−2). A structural disorder in irradiated samples has been investigated by means of selective chemical etching (SCE) and X-ray diffraction (XRD) in combination with the material layer-by-layer removal. Character of lattice deformation in the double-irradiated sample gives an evidence of subsurface region’s swelling. Strong lattice distortion has been found in the region of Bi ion ranges at the depth of about 30 μm. The nature of this effect is discussed.

Rutherford backscattering and transmission electron microscopy (TEM) are used to study distributions of impurities and structure of the GaSb + Si nanocomposites in several regimes of ion implantation and thermal processing. It is demonstrated that the hot implantation and annealing lead to a significant loss of impurity and the shift of the maximum concentration of impurity atoms toward the surface. The TEM data prove the formation of nanocrystals with sizes ranging from 20 to 100 nm, dislocation defects, and residual mechanical stresses. Raman spectroscopy is used to study the structure and phase composition of experimental silicon samples containing various nanocrystalline impurities.

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.

Results of comprehensive investigations of nanostructed TiN and MoN single-layer coatings as well as multilayer coatings consisting of TiN/MoN alternating layers have been considered. The coatings have been deposited by a promising modern method of cathode-arc evaporation (vacuum-arc method). The elemental and phase compositions of coatings, their tribological and physico-mechanical properties: friction coefficient, wear, adhesion, hardness, and elastic modulus have been studied and the mechanisms of the coatings fracture have been discussed.

Multilayered nanostructured coatings consisting of MoN and CrN alternating layers have been considered. The coatings obtained by arc-vacuum deposition in 3 series with different bias potential. The thickness of bilayers has been varied from micro (1.73 μm) to nanosizes (36÷41 nm). Parameters of deposition have been changed, such as bias potential from −20 V to −300 V and chamber pressure from 7×10−4 to 3×10−3 Torr. An element and structural analysis performed with XRD, SEM (with EDS), RBS, SIMS methods has shown well properties of obtained coatings, with clearly allocated layers of CrN and MoN. It is found formation of mononitride CrN and Mo 2 N with cubic lattice NaCl-type. Decreasing of bilayers thickness to (36÷41) nm has provided high hardness (38÷42) GPa and wear resistance. Remarkable that increasing of chamber pressure leads to increase of wear resistance.

SiO2/Si structures have been irradiated with 133 MeV Xe+17 ions at fluencies of (1010–5 × 1014) cm−2. The structure transformation and light-emitting properties of irradiated SiO2 films were studied using RS, SEM, TEM and PL techniques as well as chemical etching in 4% solution of hydrofluoric acid (HF). An intensive photoluminescence in visible range was registered from the samples irradiated at a fluence of 1014 cm−2 and higher. Simultaneously, it was found a drastic increase of SiO2 etch velocity in HF solution for the irradiated samples. Annealing (1100 °C, 2 h) of irradiated samples resulted in PL quenching and etch velocity recovery practically to the value of non-irradiated SiO2. It was concluded that radiative oxygen deficient centers are responsible for the PL appearance. It was also shown that the etch velocity ratio of the irradiated and virgin SiO2 in 4%-HF (Virr/Vvirgin) can be used in order to estimate the radiation damage in SiO2 matrix irradiated with high fluencies of swift heavy ions.

The effect of the additive of the third element (Al, Cr or Si) to titanium nitride coatings deposited using reactive magnetron sputtering on their hardness and tribological behavior is studied. The regularities of the formation of the coatings, as well as the influence of conditions of deposition on their final composition and characteristics, are considered; recommendations on producing the TiN-based coatings with the enhanced performance characteristics are given. The tribotests of these coatings are performed and discussed. When using the aluminum additive and keeping optimum conditions of deposition, the effect of enhancing the performance characteristics of the TiN coating is observed.