High-entropy alloys are promising materials for novel thin-film resistors since they have high resistivity and a low-temperature coefficient of resistivity (TCR). In this work, a new high-entropy thin-film CoCrFeNiTi_x was deposited on a Si/SiO₂ substrate by means of magnetron sputtering of the multi-component target produced by hot pressing of the powder mixture. The samples possessed a thickness of 130–230 nm and an amorphous atomic structure with nanocrystallite traces. This structure persisted after being annealed up to 400 °C, which was confirmed using X-ray and electron diffraction. The film had a single-phase structure with a smooth surface and a uniform distribution of all elements. The obtained film served for microresistor elaboration, which was produced using the lithography technique and tested in a temperature range from −60 °C up to 200 °C. Resistivity at room temperature was estimated as 2.37 μOhm·m. The results have demonstrated that TCR depends on temperature according to the simple linear law in a range from −60 °C up to 130 °C, changing its value from −78 ppm/°C at low temperatures to −6.6 ppm/°C at 130 °C. Such characteristics show the possibility of using these high-entropy alloy films for resistive elements in contemporary and future micro-electronic devices.

In this study, hard wear-resistant Ti-Si-C coatings were deposited on Cu-Cr materials to improve their performance as sliding electrical contact materials. A ceramic disk composed of Ti₃SiC₂ and TiC phases was used as a target for DC magnetron sputtering to deposit the coatings. The influence of the power supplied to the magnetron on the chemical composition, structure, and friction coefficient of the coatings was examined. The coatings demonstrated high hardness (23–25 GPa), low wear rate (1–3 × 10⁻⁵ mm³/N/m) and electrical resistance (300 μOhm·cm), and fair resistance to electroerosion. The coating deposited at 450 W for 30 min displayed optimal properties for protecting the Cu-Cr alloy from the arc effect.

Chalcogenide vitreous semiconductors (ChVSs) find application in rewritable optical memory storage and optically switchable infrared photonic devices due to the possibility of fast and reversible phase transitions, as well as high refractive index and transmission in the near- and mid-infrared spectral range. Formed on such materials, laser-induced periodic surface structures (LIPSSs), open wide prospects for increasing information storage capacity and create polarization-sensitive optical elements of infrared photonics. In the present work, a possibility to produce LIPSSs under femtosecond laser irradiation (pulse duration 300 fs, wavelength 515 nm, repetition rate up to 2 kHz, pulse energy ranged 0.03 to 0.5 μJ) is demonstrated on a large (up to 5 × 5 mm²) area of arsenic sulfide (As₂S₃) and arsenic selenide (As₂Se₃) ChVS films. Scanning electron and atomic force microscopy revealed that LIPSSs with various periods (170–490 nm) and orientations can coexist within the same irradiated region as a hierarchical structure, resulting from the interference of various plasmon polariton modes generated under intense photoexcitation of nonequilibrium carriers within the film. The depth of the structures varied from 30 to 100 nm. The periods and orientations of the formed LIPSSs were numerically simulated using the Sipe–Drude approach. A good agreement of the calculations with the experimental data was achieved.

The thermal stability of a CoCrFeNiCu high-entropy alloy (HEA) is studied in the course of prolonged annealing in a temperature range of 873–1273 К for 204 days. The alloy, which is prepared by mechanochemical alloying of metal powders in a planetary-type ball mill for 120 min in an Ar atmosphere, is the substitutional solid solution based on a high-entropy phase with a face-centered cubic structure (fcc). During annealing for 1–3 days, the initial fcc phase decomposes into the copper-enriched fcc1 phase and copper-depleted fcc2 phase, which have close lattice parameters, namely, 3.60 and 3.57 Å, respectively. Throughout the time of annealing, the redistribution of intensities of diffraction reflections of the fcc1 and fcc2 phases occurs, the dynamics and character of which depend on the temperature and time of process. After first three days and to the end of heat treatment, the HEA retains the fcc substitutional solid solution structure, and the lattice parameters of the formed fcc phases retain unchanged with an accuracy of 0.1% up to 204 days. The quinary matrix formed after annealing has the Co_0.23Cr_0.23Fe_0.23Ni_0.23Cu_0.08 chemical composition and is stable. Throughout the heat treatment time, the increase in the grain size is observed. First, when the active transformation of the structure occurs, the grain size increases rapidly; after that, during annealing for 1 to 30 days, the grain growth is limited by the diffusion of atomic components. During very prolonged annealings, the grain growth slows down more.

Germanium–cobalt–indium nanostructures were synthesized via cathodic electrodeposition from aqueous complex solutions of Ge (IV) and Co (II) with drop-like indium crystallization centers. This approach features simplicity, avoids heating and allows using cheaper GeO₂ instead of pure Ge as starting material. Further, in this case, target nanostructures grow directly upon the substrate. Various analytical methods (scanning electron microscopy, transmission electron microscope and X-ray diffraction) were used for characterization of the nanostructures under study. The samples obtained consist of an array of globular particles of 200 to 800 nm, with nanowires in between. The globules, in turn, contain primary particles of 5 to 10 nm consisting of cobalt, germanium and oxygen. Nanowires consist of germanium and indium. The electrochemical properties of the above-mentioned nanostructures were assessed with cyclic voltammetry and galvanostatic cycling. The germanium–cobalt–indium nanostructures are characterized by a high specific capacity upon lithium insertion, which is approximately 1350 mAh/g at C/8, and a high Coulomb cycling efficiency in the first cycle (approximately 0.76). Germanium–cobalt–indium nanostructures show the ability to operate at high rates up to 16 C at a wide temperature range from +20 to −35 °C.