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Abstract In the development of promising ULIS scaling technologies, one of the key roles is played by porous dielectrics with a low permittivity used to isolate interconnects in a metallization system. Condensation of gaseous products in the pores of such films makes it possible to solve the most important problem that prevents the integration of such films, to carry out low-damage plasma etching. However, methods for studying porosity are also based on the study of the adsorption isotherm during condensation in film pores. Therefore, the study of adsorption in pores is one of the most important practical problems arising in the creation of dielectrics with a low permittivity and the study of low-damaging methods for their structuring. The method of ellipsometric porosimetry is an easy-to-implement and accurate approach for obtaining an adsorption isotherm; however, its further analysis and determination of the pore size distribution are reduced to solving an integral equation and is an ill-posed problem. In this paper, we propose to apply Tikhonov’s regularization method to solve it. The method is verified on model data and used to study a low-k dielectric sample with an initial thickness of 202 nm and a permittivity of 2.3 based on organosilicate glass.

Abstract In this review of experimental studies, the retention time and endurance of memristor RRAM memory elements based on reversible resistive switching in oxide dielectrics are studied. The influence of external parameters—switching pulses and ambient temperature—as well as internal factors—evolution of the concentration of oxygen vacancies in the filament region, the material, structure; the thickness of the active dielectric layer, material of metal electrodes on the long-term stability of high resistance state (HRS) and the low resistance state (LRS) of the memristor is discussed.

The selectivity of the reactive ion etching of functional materials included in the device structures of nanoelectronics with respect to the mask of a negative e-beam resist based on hydrogen-silsesquioxane (HSQ) is studied. The formation of nanostructures with sub-50-nm critical dimensions under the HSQ mask is studied for a number of materials: monocrystalline silicon, metallic Ta layers, dielectric SiO2 layers, Al2O3, HfO2, Si3N4, and low-k porous dielectric based on organosilicate glass (OSG) on silicon substrates. It is established that HSQ resist masks can be used to manufacture prototypes of micro- and nanoelectronic devices with topological dimensions up to 10 nanometers using a wide range of materials, including creating structures with relatively high aspect ratios with an absolute thickness of the layers of functional materials of tens of nanometers.

The phase equilibria in the NaF–AlF3–CaF2 system with a fixed sodium-fluoride-to-aluminum fluoride molar ratio of 1.17 are studied. This composition is eutectic; its melting temperature is 680°C. Samples were prepared using individual salts. Aluminum fluoride is purified from oxygen-containing impurities using ammonium fluoride and glassy carbon crucible. The study is performed by thermal analysis, differential scanning calorimetry (DSC), and X-ray diffraction (XRD). To perform XRD and DSC analyses, the melt is frozen on an alumina stick in order to prepare quenched samples. The liquidus temperatures are determined by measuring cooling curves, which are plotted on the thermopower–time coordinates using an APPA 502 multimeter. The solidus temperatures were studied with a STA 449C Jupiter (NETZSCH, Germany) synchronous thermal analyzer, which is calibrated using pure salt supplied by NETZSCH. A single-crystal sapphire is used to calibrate the sensitivity. A MiniFlex 600 X-ray (Rigaku, Japan) diffractometer equipped with a copper anode is used for XRD studies to determine the phase composition of samples. A quasi-binary (NaF–AlF3)eut–CaF2 phase diagram is constructed. Seven samples are studied; in this case, the potassium fluoride content is varied from 0 to 6.5 mol %. The diagram is characterized by a eutectic point at a calcium fluoride content of 0.5 mol % and a temperature of 675°C. The phase diagram also has two peritectic points, which correspond to the decomposition of the complex Ca2AlF7 and NaCaAl2F9 compounds. When reaching the eutectic point, the liquidus temperature abruptly increases as the calcium fluoride content increases. This results in the low solubility of CaF2 in the low-melting NaF–AlF3 eutectic at temperatures below 750°C. The data obtained are of interest for developing a technology of low-temperature electrolysis of aluminum.

Mechanical properties of the metal from drums of boilers at the Starobeshevskaya and the Lugansk thermal power plants (TPPs) were investigated. According to the results of the standard technical diagnostics and a strength analysis, both drums comply with the applicable regulatory requirements. At the Starobeshevskaya TPP, the drum was ruptured during a hydraulic test. It was found that this was caused by the low impact strength of the metal at room temperature. The objects of the investigation were fragments of the ruptured drum and a “plug” cut out of the shell during a scheduled inspection. An attempt is made in this paper to assess the state of equipment metal based on the results of tests on subsize Charpy specimens. It has been demonstrated that when standard Charpy specimens (10 × 10 × 55 mm) cannot be made but impact bend tests have to be performed, the brittle-to-ductile transition temperatures for standard Charpy specimens may be obtained in testing 2 × 8 × 55 mm specimens. The correlation developed to relate the test results from subsize specimens to standard Charpy specimen enables us to assess in the first approximation the fitness for service of the metal to prolong the equipment’s service life. The rupture surface of subsize Charpy specimens has almost the same appearance as that of standard specimens. The temperature dependence of ductile component of subsize specimens agrees well with the corresponding dependence for standard Charpy specimens. To integrate the test data into a single database, it is desirable to derive a correlation to relate the critical brittleness temperature from a subsize specimen test to the critical brittle temperature from standard Charpy specimens.

Using the method of quantum-chemical modeling of a system of gold nanoparticles on a graphite substrate with various defects, a decrease in the density of states of gold atoms during the adsorption of hydrogen near the interface is shown. Substrate defects, such as vacancies and cutoffs of the graphene plane, contribute to a decrease in the density of states during the adsorption of hydrogen atoms.

Methanol conversion to dimethyl ether using alumina-modified silica gel based adsorbents was studied. ASM, ASM VS, BASF KC-Trockenperlen H, BASF KC-Trockenperlen WS, and NIAP-AOS adsorbents used in industrial adsorption installations for natural gas treatment were tested. The composition and structural characteristics of the commercial adsorbents were characterized by X-ray fluorescence and X-ray diffraction analysis and by low-temperature nitrogen adsorption and were correlated with the catalytic activity. The dependences of the concentration of the dimethyl ether formed on the reaction temperature and carrier gas flow rate through the adsorbents were determined. Methanal, diethyl ether, acetone, methyl acetate, and ethanol were identified as by-products of methanol conversion on the tested adsorbents. The results of thermocatalytic transformations of methanol on the adsorbents demonstrated good prospects for using ASM silica gel modified with 4.6% aluminum oxide for natural gas treatment in industry; its use allows reduction of the methanol emission to the atmosphere. At 290°С and flow rate of nitrogen containing 197 ± 3 mg L–1 methanol of 1200 mL min–1, the methanol conversion on ASM 1 adsorbent reached 91 wt %, and the dimethyl ether yield reached 49 wt %.

At present, there are two Micromegas detector production sites at the Dzhelepov Laboratory of Nuclear Problems, Joint Institute for Nuclear Research (DLNP JINR). The first site provides the production and testing of Micromegas chambers for the outer part of the large sectors (LM2) of the New Small Wheels for the ATLAS Muon spectrometer. It will produce and test 64 double-sided readout panels with a surface area of 3 m2 each and 32 Micromegas chambers based on them. Component materials for all project participants are centrally delivered from CERN. The second site is for a complete production cycle and intended for the research and development of Micromegas detectors with widths reaching 60 cm.

New hybrid N-acetonylpyridinium, N-(ω-iodoacetonyl)pyridinium, and N-acetonyl-2,6-dimethylpyridinium halobismuthates I–VII have been synthesized and structurally characterized. A preparative method of synthesis is proposed for compounds I, III, and VII, and some individual crystals have been managed to separate and characterize for compounds II, IV–VI. A new type of {K[BiBr6] $$\} _{n}^{{2n - }}$$ 1D-chains with K+ cations has been revealed in the structure of [C8H10NO]2K[BiBr6] (II). N-acetonyl-2,6-dimethylpyridinium bromobismuthates [C10H14NO]3[Bi2Br9] V and VI (space group P21/n) are polymorphs of similar structure. Iodobismuthates [C8H10NO]4[Bi4I16] (III) and [C10H14NO]4[Bi4I16]⋅0.69I2 (VII) are built of [Bi4I16]4– anions, and [Bi4I16] moieties in the structure of VII are linked into a 1D-anionic chain by molecules I2.

The results of studies of the effectiveness of the optimal radar altimeter when tracking targets moving along trajectories of varying complexity are presented. The tracking system of the altimeter is obtained in the first part of this article by the local minimization of the quadratic-biquadratic quality functional.

Parameterizations of the electromagnetic form factors of $$f_{1}(1285)$$ meson are considered. Using these parameterizations theoretical predictions for the total cross section of the direct $$f_{1}(1285)$$ meson production in $$e^{+}e^{-}$$ annihilation, $$\sigma(e^{+}e^{-}\to f_{1}(1285))$$ , are obtained.

Complex oxides with pronounced proton transfer occupy a special place in modern solid-state ionics and high-temperature electrochemistry, being of great interest from both fundamental and applied viewpoints. Doped barium cerate-zirconates (BaCeO3–BaZrO3) are positioned as the most conductive oxides, and therefore they are widely used in various solid oxide devices. However, the presence of a highly basic alkaline earth cation leads to an insufficient chemical stability of cerate-zirconates in real working conditions. In this regard, designing new proton-conducting oxides with improved chemical stability is an actual issue. Some lanthanum-containing perovskites, LaBO3 (where B is a trivalent element), can be considered as stable analogs since they contain no alkaline and alkaline earth elements in their basic structures. This review aims at a critical analysis of the properties of these compounds and the prospects for their application as electrolyte membranes for solid oxide fuel cells, pumps, and sensors. The paper provides basic information about LaBO3-based compounds, highlights their advantages in comparison with other representatives of proton conductors, and indicates disadvantages acting as limiting factors for the application of lanthanum-containing protonic electrolytes with a perovskite structure in electrochemical devices.

A method of obtaining detonation nanodiamonds from tetryl by means of blasting the latter in a water shell with the explosive/water mass ratio of 1/(10–14) is developed. The proposed method ensures the yield of the target product in the amount of 6–7 wt.% of the initial mass of the reagent with the content of nanodiamonds in the resultant batch mixture equal to 57 $$\,\pm\,$$ 6 wt.%. It is demonstrated that the use of individual explosives offers some advantages over the known multicomponent mixtures in terms of cost efficiency and safety of the charge preparation process.

The (CsCl–NaCl–KCl)eut–IrCl3 melt is promising for the production of iridium coatings and composites. The liquid temperature and the electrical conductivity are determined for several compositions of the melt by thermal analysis and impedance spectroscopy. The temperature ranges of liquidus (753–983) ± 5 K and solidus (751–755) ± 4 K are established and the corresponding parts of the phase diagram for the quasi-binary system (CsCl–NaCl–KCl)eut–(0–2.12 mol %) IrCl3 is plotted. The lowest liquidus temperature is shown to be observed for the melt containing 1.4 mol % IrCl3. The increase in the liquidus temperature in the molten mixtures with more than 1.5 mol % IrCl3 is explained by the formation of the Cs3IrCl6 compound, which was detected by XRD analysis. The electrical conductivity of the melts (in the homogeneity region) is found to linearly decrease as the temperature decreases or the IrCl3 concentration increases. The coefficients that describe the temperature dependences of the electrical conductivity of the (CsCl–NaCl–KCl)eut–(0–2.12 mol %) IrCl3 melts are determined. For all the studied iridium-containing compositions, the average temperature coefficient is (2.35 ± 0.02) × 10–3 Ω–1 cm–1 K–1. The addition of 1 mol % IrCl3 leads to a decrease in the electric conductivity by about 7%. It is found that the operating temperature can be decreased to ~800 K in the melt with iridium trichloride concentrations of 1.4–1.5 mol %; the process temperature can be varied from 850 K to 1030 K at lower and higher IrCl3 contents depending on the electrodeposition conditions.

Mossbauer spectroscopy is used to study the characteristic features of the crystal lattice dynamics in powdered single crystals of Fe1.75V0.25BO4 warwickite in the temperature range of 4.2–505 K. The Debye temperature (ΘD = 260 K) is determined from the temperature dependence of the probability of the Mossbauer effect in the thin absorber approximation. It is found that the electron delocalization related to the fast electronic transfer between neighboring Fe3+ and Fe2+ cations takes place in the temperature range of 260−505 K. As a result, iron cations exhibiting the mixed valence (Fe2.5+) arise. This process correlates with a change in the elastic properties of the lattice. Such correlation leads to a sharp decrease in the recoil-free absorption of γ‑ray photons by the crystal lattice in the range of 260–400 K.

The reactions of 3-arylamino-1,4-naphthoquinone-4-oximes with 2,2-dihydroxyindane-1,3-dione proceed without involving the oxime group and lead to (6E)-5-arylamino-4b,11b-dihydroxy-6-hydroxyimino-4b,5-dihydrobenzo[f]indeno[1,2-b]indole-11,12(6H,11bH)-diones. The reactions of 2-arylamino(alkylamino)-1,4-naphthoquinone-4-oximes with 2,2-dihydroxy-1,3-indandione involve the oxime group and lead to 6-[arylamino(alkylamino)]-6b,11b-dihydroxy-5,7-dioxo-5,6b,7,11b-tetrahydrobenzo[g]indeno[1,2-b]indole 12-oxides.

A numerical model of the evolution of the trench profile during cryogenic etching in SF6/O2 plasma based on the cellular representation of the surface state, the Monte Carlo method for calculating particle fluxes, and the scheme of delayed desorption of reaction products is proposed. This description combines the advantages of the cell method (the ability to describe phenomena of a stochastic nature) and the string method (parameterization of the model in terms of physically observable quantities). The consistency of the model for etching silicon and silicon oxide in a fluorine-containing plasma, as well as etching in a SF6/O2 mixture at different temperatures is demonstrated. Spontaneous etching of silicon under the action of fluorine radicals, ion-stimulated etching, surface passivation in plasma containing oxygen radicals are simulated. A model that describes the temperature dependence of the etching character is proposed.

A history of the topic is presented. First, information is given about the development of supersonic aviation. Then, the history of studying the phenomenon of sonic boom generated by flying bullets and projectiles is briefly described. The results of the renowned aeroacoustic scientists K. Doppler and E. Mach are presented, as well as little-known historical facts found in old foreign sources. The need for correct use of the term “sonic boom” is pointed out, which is not limited to aviation acoustics problems, but is inherent to many natural and technogenic phenomena. A 100-year priority of the acoustic effect over its weaker optical counterpart, Vavilov–Cherenkov radiation, is mentioned. Problems related to calculating the generation of perturbations in the interaction of transonic and supersonic flows with real bodies are described: the need to take into account the details of the shape of the aerodynamic profile, peculiarities in the behavior of the boundary layer, the formation of shock waves, generation of flow turbulence, and the kinetics (relaxation and dissociation) of atmospheric gases. The phenomenon of wave resonance, responsible for the formation of the boom when breaking the sound barrier, is discussed. Nonlinear processes in N-wave formation in the propagation of complexly shaped signal are described. The influence of the main effects distorting the N-shaped profile is explained: diffraction, focusing, and multiple relaxation phenomena broadening the shock front. The theory of N-waves in an inhomogeneous medium is discussed. Examples of ray patterns in a standard atmosphere and in the region behind the turbulent boundary layer are constructed. Calculation methods based on nonlinear geometric acoustics and nonlinear quasioptics approximations are presented. Problems related to the consequences of sonic booms and their harmful effects on the environment, structures, and living organisms are indicated. An extensive bibliography and a list of fundamental reviews in the domestic and foreign literature are presented.