In order to explore the effect of alloying on the microstructures and mechanical properties of AlCoCrFeNi_2.1 eutectic high-entropy alloys (EHEAs), 0.1, 0.2, and 0.3 at.% V, Mo, and B were added to the AlCoCrFeNi_2.1 alloy in this work. The effects of the elements and contents on the phase composition, microstructures, mechanical properties, and fracture mechanism were investigated. The results showed that the crystal structures of the AlCoCrFeNi_2.1 EHEAs remained unchanged, and the alloys were still composed of FCC and BCC structures, whose content varied with the addition of alloying elements. After alloying, the aggregation of Co, Cr, Al, and Ni elements remained unchanged, and the V and Mo were distributed in both dendritic and interdendritic phases. The tensile strengths of the alloys all exceeded 1000 MPa when the V and Mo elements were added, and the Mo0.2 alloy had the highest tensile strength, of 1346.3 MPa, and fracture elongation, of 24.6%. The alloys with the addition of V and Mo elements showed a mixed ductile and brittle fracture, while the B-containing alloy presented a cleavage fracture. The fracture mechanism of Mo0.2 alloy is mainly crack propagation in the BCC lamellae, and the FCC dendritic lamellae exhibit the characteristics of plastic deformation.

This article presents experimental results on the study of the current-voltage characteristics of strongly compensated n- and p-type silicon samples diffusion-doped with zinc at a temperature of 80 K. The current-voltage characteristics of the studied samples contain both sublinear and superlinear sections. Several (up to eight) characteristic areas were found, the number of which depends on the degree of illumination, temperature, and electrical resistivity of the sample. Under certain conditions, there is an alternation of sections of the current-voltage characteristic with negative differential conductivity of the N- and S-type, behind which current instabilities with an infra-low frequency are observed. The appearance of sections of the current-voltage characteristic with a quadratic dependence is explained by the presence of fast and slow recombination centers associated with zinc nanoclusters, and sublinear sections are explained in terms of the theory of the "injection depletion effect". The formation of nanoclusters with the participation of zinc ions was confirmed by atomic force microscopy studies.

This article presents the results of experimental studies on the formation of nanosized objects in single crystals of silicon ion-implanted with manganese ions with an energy of 40 keV at various doses. The formation of nanosized objects was determined by atomic force microscopy (AFM) and Raman spectroscopy (RS). It was found that in the Raman spectrum of non-implanted samples there are peaks with a wave number of 520 cm^-1 characteristic of pure silicon associated with the crystalline phase and satellites with frequencies 301 cm^-1, and 971 cm^-1. The band with a wave number of 971 cm^-1 corresponds to the main band of the tetrahedral bond in silicon. The intensity of this peak depends on the sample thickness. When the sample thickness changes from 200 μm to 3 mm, the intensity of this peak decreases by almost two times. And in the Raman spectra of ion-implanted samples, several bands with different intensities are observed, and their number and intensity strongly depend on the implantation dose. It has been suggested that the observed peaks are possibly associated with radiation defects and nanosized formations. This assumption was verified using AFM investigation. The AFM images show various nanosized objects, apparently associated with manganese ions.

P-Si substrate was cleaned by chemical means. After the cleaning, iron thin film was deposited on the silicon substrate by electron beam evaporation method with high purity Fe target. Then, the roughness parameters of the sample after chemical cleaning and after obtaining a thin layer were compared. Surface roughness measurement of the iron thin film in the nanometer scale can be accurately determined using the AFM. Apart from the average roughness, all the roughness parameters of the surface increased. The average roughness, average height, root mean square roughness, and other parameters are used to analyze surface morphology.

This article presents experimental results on the technology of obtaining and studying the lateral photoelectric effect (LPE) in hybrid structures (HS) of the Fe/SiO2/p-Si and Fe/SiO2/n-Si types. The technology for obtaining such HS consists of two parts: firstly, obtaining compensated (C), highly compensated (HC), and over-compensated (OC) samples of Si . Secondly, obtaining HS Fe/SiO2/p-Si and Fe/SiO2/n-Si. Based on the results, it is shown that sufficiently good HS has been obtained. Experiments on the study of LPE have shown that in the studied HS there is a pronounced manifestation of the lateral photoelectric effect, the magnitude and nature of which strongly depend on the type of conductivity and resistivity of the compensated silicon. The observed features are explained by the fact that in С, HC, and OC silicon samples, impurities that create deep levels in the silicon band gap form various multi-charged complexes that modulate the energy band of silicon, which lead to significant changes in its physicochemical and generation-recombination properties, which underlies the observed effects. Based on the LPE studies, depending on the contact distance, it is possible to determine the numerical values of the diffusion lengths of the minor current carriers (Lp and Ln), their lifetimes (τp and τn), and diffusion coefficients (Dp and Dn) on the substrate material.