In this work, we studied the formation of silver nanoparticles on silicon substrates by irradiating thin silver films with Ar+1000 cluster ions with an energy of 10 keV. The topography of the film surface was studied using scanning electron microscopy. The dependence of the particle size and their surface density on the ion fluence was described, which opens a way for controlling the geometric parameters of the particles. Particle formation was considered as a result of two competing processes: sputtering and surface migration of the film atoms. Irradiation with cluster ions at oblique incidence leaded to formation of the particles of elongated shape, with the particle height being comparable to the initial film thickness. Applicability of the particles to surface enhanced Raman spectroscopy was characterized using the dye rhodamine 6 G.

The paper presents experimental data on the kinetics of charging and cathodoluminescence (CL) of single-crystal sapphire under electron irradiation. We give a new explanation for the previously found effect of the delay in surface potential development during charging of single-crystal sapphire by an electron beam, and simultaneous increasing of CL intensity. Such a delay can be explained by a gradual accumulation of negative charge in the sapphire volume, which volume is larger than the initial electron-solid interaction region, together with high secondary electron emission. Such charge spreading leads to an increase in the CL intensity throughout the surface potential delay. A hypothesis is suggested that the delay time is determined by the initial number of electron traps. Subsequently, when sufficient charge is accumulated, a retarding electric field arises inside the sample, leading to a decrease of the region of negative charge localization and almost complete neutralization of the positive charge.

Comprehensive structural studies of thin island Al films with a thickness of 20–50 nm deposited by magnetron sputtering on Si(111) substrates in an argon plasma at a pressure of 6 × 10–3 mbar and a temperature ranging from 20 to 500°C are presented. The morphology and microstructure of the films are studied using XRD, SEM, EDS, and TEM methods. It is found that most of the islands are Al 001 and Al 111 crystallites with lateral sizes of 10–100 nm, differently conjugated with the Si(111) substrate. At room temperature of the substrate, only Al 001 crystallites are epitaxially formed on it. The epitaxial growth of Al 111 crystallites is predominant as the substrate temperature increases above 400°C. The influence of the temperature of the Si(111) substrate on the process of epitaxial growth of crystallites, the dynamics of their shape, and structural perfection is shown. It is found that crystallites epitaxially connected to the substrate experience deformation at ε = 7 × 10–3 and ε = –2 × 10–3 for Al 001 and Al 111, respectively. It is shown that for thin island Al films on Si(111), the dependence of the number of crystallization centers and the particle growth rate on the supercooling temperature is consistent with the band model of crystallization. At the same time, a shift in the characteristic temperatures for the zone boundaries is observed due to the properties of the substrate. This must be taken into account when engineering the surface morphology and structural perfection of crystallites in Al island magnetron films.

A method is proposed for measuring high-voltage charging potentials of dielectrics under ion irradiation by shifting the boundary of the bremsstrahlung X-ray spectrum. Since there is no bremsstrahlung output during Xe+ ion irradiation, it was proposed to use a probing electron beam to generate bremsstrahlung X-rays. To eliminate the effect of charge compensation on the surface, the value of the current of the probing probe of electrons was selected. The values of the equilibrium charging potentials of Al2O3 ceramics, Al2O3 sapphire, SiO2, and Teflon are obtained at different ion irradiation energies. The data obtained are compared with the results of spectrometric studies. Keywords: dielectric charging, ion irradiation, FIB-SEM, surface potential measurement.

The results of complementary studies of Al films grown by magnetron sputtering at room temperature are presented. The films were obtained on standard Si(111) substrates without and with a ∼20 nm aluminum (homobuffer) layer preliminarily grown on their surface at 400°C. The interdependence of the morphology, microstructure, and hardness of Al films on the state of the substrate surface was studied by the HRXRR, XRD, SEM, EDS, AFM, and Nano Indenter (ASTM) methods. It is shown that the formation of homobuffer layers on the substrate surface makes it possible to control the structural and mechanical properties of thin aluminum films.

Nitinol is an alloy of roughly equiatomic nickel and titanium, having shape memory and widely used in many applications, such as aerospace, automotive, biomedical and others. One of techniques for its treatment is plasma or ion beam irradiation. In the work we investigated surface composition and topography of the alloy formed by ion and cluster ion bombardment. A strong enrichment of the surface with nickel is detected, which does not agree with contemporary ideas about preferential sputtering. The results were compared with other known results in the area, and the processes occurring under ion irradiation of compound materials were discussed. The role of ambient oxygen in the steady state surface composition establishing is described.

Kinetics of single crystal MgO electrization showed a delay in the surface potential establishment. A number of processes taking place in the surface electrization and, in their turn, influenced by it, are discussed: secondary electron emission, accumulated charge distribution and spreading in the sample, modification of defects in the sample by the electron beam. The evolution of cathodoluminescence spectra was recorded during the irradiation process, showing both increases and decreases in intensity. A synergetic effect was suggested to explain the subthreshold generation of defects by the electron beam.

The selectivity of the reactive ion etching of silicon using a negative electron resist AR-N 7520 mask was investigated. The selectivity dependencies on the fraction of SF6 in the feeding gas and bias voltage were obtained. To understand the kinetics of passivation film formation and etching, the type and concentration of neutral particles were evaluated and identified using plasma optical emission spectroscopy. Electron temperature and electron density were measured by the Langmuir probe method to interpret the optical emission spectroscopy data. A high etching selectivity of 8.0 ± 1.8 was obtained for the etching process. The optimum electron beam exposure dose for defining the mask was 8200 pC/m at 30 keV.

The results of a study of the structural features and electrical properties of the end-to-end thermomigration (ThM) of the p-channels of Si(Al) in a silicon wafer are presented. Structural studies are carried out using X-ray methods of projection topography, diffraction reflection curves, and scanning electron microscopy (SEM). It is shown that the channel-matrix interface is coherent without the formation of misfit dislocations. The possibility is shown of using an array of the ThM of the p-channels of 15 elements for the formation of a monolithic photoelectric solar module in a Si(111)-based silicon wafer of p-channels 100 µm wide with walls in the plane ( 11̅0) . The monolithic solar module has a conversion efficiency of 13.1

In this work, we studied the effect of 350 keV proton irradiation with two different fluences of 1013 cm-2 and 1015 cm-2 on the cathodoluminescence (CL) spectrum of GaN. Three lines were observed in the CL spectra of virgin and proton pre-irradiated samples -band edge line (3.4 eV), blue line (2.8 eV) and yellow line (2.15 eV). A strong decrease in the CL intensity for samples pre-irradiated by protons, especially at high proton fluence of 1015 cm- 2, is shown. The evolution of the cathodoluminescence spectra during electron irradiation demonstrates a further decrease in all line intensities. It was shown that virgin and proton pre-irradiated GaN samples were not charged under electron irradiation. The cathodoluminescence signal drop can be caused by a decrease in the concentration of initial luminescence centers associated with intrinsic and impurity defects due to their trans-formation under proton bombardment and electron-stimulated diffusion implanted H+ ions.

A novel method is proposed to measure the charging potential of dielectric targets under medium energy electron irradiation in a scanning electron microscope. The method is based on the measurement of backscattered electron signals by standard semiconductor or scintillation detectors. The signal is pre-calibrated by grey scale levels on the SEM screen. The detector signal is made up with backscattered and secondary electrons which are accelerated in the electric field created above the dielectric surface under irradiation.

The results of complementary studies of Al films grown by magnetron sputtering at room temperature are presented. The films were obtained on standard Si(111) silicon substrates without and with a ~20 nm aluminum (homobuffer) layer preliminarily grown on their surface at 400°C. The interdependence of the morphology, microstructure, and hardness of Al films on the state of the substrate surface was studied by the HRXRR, XRD, SEM, EDS, AFM, and Nano Indenter (ASTM) methods. It is shown that the formation of homobuffer layers on the substrate surface makes it possible to control the structural and mechanical properties of thin aluminum films.

The formation of polyene-polyyne-based nanocomposites by dehydrohalogenation of the drop-cast-deposited polyvinylidene fluoride, assessment and ion-induced tailoring of their gas sensing properties are reported. The investigated structure was analyzed by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy, transmission electron microscopy and Fourier-transform infrared spectroscopy, revealing the thickness-dependent incomplete dehydrofluorination of the structure and its porosity induced by KOH treatment. The polyene-polyyne structures modified by low-energy Ar+ were studied by SEM and Raman spectroscopy, which showed the morphology variation, the shortening of chains and the graphitization of samples. The resistive gas sensing properties of the samples were analyzed at room temperature, revealing selective sensing of ammonia vapor by non-irradiated sample and the enhancement of the sensing properties for ethanol and water vapor after ion irradiation. With the ion dose enlargement, the change in the sensing response from electrical conductivity increase to decrease was observed for ammonia and ethanol, allowing us to discuss the origin and tunability of the sensing mechanism of the samples.

— New possibilities for the mode of detecting backscattered electrons in a scanning electron microscope (SEM) are presented. The technique for determining the chemical composition of the probed area of the sample using the precalibrated scale of the SEM’s gray screen has been further developed. Simple relationships are presented for practical application in finding the thicknesses of thin films on a massive substrate. The parameters of the double layer of the film nanostructure on the substrate are determined, that is, depth and thickness of subsurface fragments of the microobject. A technique is proposed for measuring the surface potential of negatively charged dielectric samples upon irradiation with medium-energy electrons.

In this paper, we develop fabrication technology and study aluminum films intended for superconducting quantum nanoelectronics using AFM, SEM, XRD, HRXRR. Two-temperature-step quasiepitaxial growth of Al on (111) Si substrate provides a preferentially (111)-oriented Al polycrystalline film and reduces outgrowth bumps, peak-to-peak roughness from 70 to 10 nm, and texture coefficient from 3.5 to 1.7, while increasing hardness from 5.4 to 16 GPa. Future progress in superconducting current density, stray capacitance, relaxation time, and noise requires a reduction in structural defect density and surface imperfections, which can be achieved by improving film quality using such quasiepitaxial growth techniques.

The coatings comprised of the nanodiamond-based and amorphous-carbon-based phases (a-C:ND coatings) are investigated. The a-C:ND coatings were synthesized by chemical vapor deposition in the arc discharge plasma (by plasma chemical deposition) at various concentrations of Ar/H2/CH4. Raman spectroscopy showed that, apart from the diamond substructure, studied coatings contain amorphous-carbon-based and polyene-based phases, while diamond phase is passivated by hydrogen to different degrees. The interplay between the deposition parameters and materials' structure is analysed. It was shown that the ordering of the amorphous substructure and the formation of the phase boundaries affect the electron transport and secondary electron emission properties. The subject of the investigation of the true secondary electron spectra for the analysis of the nanostructured carbon materials is analysed. It was shown that the change of the polyene fraction in the structure of the samples leads to the variation of the ratio of field emission and thermionic emission. The influence of the structure and phase composition of the samples on their electron emission properties is investigated. In particular, their effect on the turn on-field, which value varied in the 9-18 V/μm range for the studied samples, is analysed.

The coatings comprised of the nanodiamond-based and amorphous-carbon-based phases (a-C : ND coatings) are investigated. The a-C : ND coatings were synthesized by chemical vapor deposition in the arc discharge plasma (by plasma chemical deposition) at various concentrations of Ar/H 2 /CH 4 . Raman spectroscopy showed that, apart from the diamond substructure, studied coatings contain amorphous-carbon-based and polyene-based phases, while diamond phase is passivated by hydrogen to different degrees. The interplay between the deposition parameters and materials' structure is analysed. It was shown that the ordering of the amorphous substructure and the formation of the phase boundaries affect the electron transport and secondary electron emission properties. The subject of the investigation of the true secondary electron spectra for the analysis of the nanostructured carbon materials is analysed. It was shown that the change of the polyene fraction in the structure of the samples leads to the variation of the ratio of field emission and thermionic emission. The influence of the structure and phase composition of the samples on their electron emission properties is investigated. In particular, their effect on the turn on field, which value varied in the 9-18 V/μm range for the studied samples, is analysed. Keywords: nanodiamond composites, polyene-like materials, electron transport, hydrogen passivation, turn-on field.

—The magnetic properties and mineralogy of titanomagnetite in the Red Sea pillow-basalt at different distances from the contact surface with water were studied. It was revealed that the composition of titanomagnetite in the pillow basalt changes from the crust deep into the pillow: the titanium content in titanomagnetite increases, while the magnesium and aluminum content decreases. Titanomagnetite in the surface layer of pillow basalt (0–2 cm) is single-phase oxidized, with a maximum oxidation degree of 0.13, and at more than 3 cm from the crust has stoichiometric composition. According to the increase in magnetic susceptibility from 0.2 up to 1.8 × 10 –2 SI, saturation magnetization from 0.026 to 0.895 A m 2 /kg and residual saturation magnetization from 0.014 to 0.296 A m 2 /kg, decrease in coercivity ( H c from 90 to 15 mT, H cr from 153 to 20 mT), as well as by observations of electron and magnetic force microscopy, it is shown that the concentration of titanomagnetite in basalt and the grain size from single-domain state to pseudo-single-domain state increase with distance from the crust. The magnetic hardness of titanomagnetite grains was found to correlate with the maximum cooling rate of basalt. The NRM of basalt varies non-monotonically with distance from the pillow surface: up to a depth of about 3 cm its growth caused by the growth of titanomagnetite concentration was revealed, then a decrease caused by a decrease in the magnetic hardness of the grains. In spite of a rather strong variation of the magnetic properties in the 0–7 cm layer of pillow basalt, the experiments by the Thellier-Coe method for all layers showed close values of the geomagnetic field paleointensity (62.5–66.0 μT) with a high value of quality coefficient q (11–45). No regularity in the value of paleointensity with distance from the cushion surface was detected.

The possibility of using polymer composite materials based on epoxy resins with the inclusion of carbon nanotubes as coatings with a low coefficient of secondary electron emission has been studied. Four types of samples were obtained: epoxy polymer, polymer composites with fillers (non-oriented and oriented carbon nanotubes, carbon soot). It is shown that the secondary electron emission yield depends on the structure of the introduced carbon filler, and polymer composites with oriented nanotubes exhibit antidynatron properties.