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The study of light-emitting defects in silicon created by ion implantation has gained renewed interest with the development of quantum optical devices. Improving techniques for creating and optimizing these defects remains a major focus. This work presents a comprehensive analysis of a photoluminescence line at a wavelength of 1240 nm (1 eV) caused by defects arising from the ion irradiation of the SiO2/Si system and subsequent thermal annealing. It is assumed that this emission is due to the formation of defect complexes WM with trigonal symmetry similar to the well-known W-centers. A distinctive feature of these defects is their thermal resistance up to temperatures of 800 °C and less pronounced temperature quenching compared to the W-line. The difference in the properties of these defect centers and W-centers can be explained by their different defect environments, resulting from the larger spatial separation between vacancies and interstitial atoms diffusing from the irradiated layer. This, in turn, is associated with the difference in the distribution of primary radiation defects during irradiation of the SiO2/Si system and silicon not covered with a SiO2 film. The patterns of changes in the WM line depending on various factors, such as the thickness of the SiO2 film, type of conductivity and impurity concentration in the original silicon, irradiation parameters, and annealing regimes, is studied and explained in detail. These findings demonstrate the benefits of this new approach when compared to previous methods. [ABSTRACT FROM AUTHOR]

The conditions for the growth of polycrystalline GeSn films on SiO2/Si(001) substrates by hot wire chemical vapor deposition are determined for the first time. The effect of the introduction of Sn into the Ge lattice on the morphology, structure, and transport properties of films is studied. GeSn films obtained at 300 °C have a uniform surface with a roughness of less than 1.0 nm. It is shown that the introduction of 5% Sn allows, without the use of recrystallization annealing, to significantly increase the hole mobility of polycrystalline GeSn films from 20 to 60 cm2 V−1 × s−1. despite the small grain size of 35 nm. Such films are of great interest for creating thin‐film transistors for active matrices' liquid crystal displays. [ABSTRACT FROM AUTHOR]

Oxovanadium(IV) etioporphyrin‐III, VO‐EtioP‐III is an important member of the petroporphyrin family. It can be isolated from crude oil or synthesized de novo from the dipyrromethene precursors, the latter being the approach we used in our research. The molecular structure of VO‐EtioP‐III was for the first time characterized by single‐crystal X‐ray diffraction. Both terminal alkyls and the axial oxygen atom protrude in the same direction relative to the molecular plane, while rear side of the molecule remains almost flat. This results in a peculiar centrosymmetric packing (space group P21/c, monoclinic system with four molecules per unit cell), in which back‐to‐back oriented molecules form the parallel‐plane dimers. The powder X‐ray diffraction data indicate that the VO‐EtioP‐III films deposited by vacuum evaporation retain a very strong texture, with all molecules standing vertically on the substrate surface. The absorption spectra of films differ from the solution spectra by a large redshift of the Soret‐ and Q‐ band (~30 nm) with hypo‐ and hyperchromic effects, respectively. The former band strongly broadens due to multiple splitting to within 350–520 nm, which is followed by a change of the color from purple (in diluted solutions) to brawn (in films or crystals). [ABSTRACT FROM AUTHOR]

Ion implantation is a promising method for the development of β-Ga2O3-based technologies and devices. However, the physical principles of ion implantation for this particular semiconductor are still at the early stage of development. One of the primary tasks is the study of electrical properties of the ion-doped layers. In this work, we have investigated the electrical parameters of layers produced by ion implantation of a shallow donor impurity—silicon—into a semi-insulating β-Ga2O3 doped with iron and having a surface orientation of (−201). It is established that the activation efficiency of the implanted impurity significantly exceeds unity after post-implantation annealing at high temperatures. This indicates that not only silicon itself contributes to conductivity, but also defects formed with its (and, probably, iron) participation are involved. The temperature dependence of electron mobility is consistent with the theoretically calculated one under the assumption that, apart from shallow donors, there are also deep defect-associated donors and acceptors. It is assumed that the established properties are specific for the case of direct Si implantation into β-Ga2O3 doped with Fe. [ABSTRACT FROM AUTHOR]

The data on electrical and photoelectric characteristics of Ga2O3/ZnGeP2 hetero-structures formed by RF magnetron sputtering Ga2O3 target with a purity of (99.99%) were obtained. The samples are sensitive to UV radiation with a wavelength of λ = 254 nm and are able to work offline as detectors of short-wave radiation. Structures with Ga2O3 film that was not annealed at 400 °C show weak sensitivity to long-wavelength radiation, including white light and near-IR (λ = 808 and 1064 nm). After annealing in an air environment (400 °C, 30 min), ZnGeP2 crystals in contact with Ga2O3 show n-type conductivity semiconductor properties, the sensitivity of Ga2O3/ZnGeP2 hetero-structures increases in the UV and IR ranges; the photovoltaic effect is preserved. Under λ = 254 nm illumination, the open-circuit voltage is fixed at positive potentials on the electrode to Ga2O3, the short-circuit current increases by three orders of magnitude, and the responsivity increases by an order of magnitude. The structures detect the photovoltaic effect in the near-IR range and are able to work offline (remotely) as detectors of long-wavelength radiation. [ABSTRACT FROM AUTHOR]

This paper reports on the preparation of xenotime-structured ceramics using the Spark Plasma Sintering (SPS) method. Y0.95Gd0.05PO4 (YPO4:Gd) phosphates were obtained using the sol-gel method. The synthesized powders were nanodispersed and were agglomerated (the agglomerates sizes were 10–50 µm). The ceramics had a fine-grained microstructure and a high relative density (98.67 ± 0.18%). The total time of the SPS process was approximately 18 min. The sintered high-density YPO4:Gd ceramics with a xenotime structure were irradiated with 132Xe+26 ions with 167 MeV of energy and fluences in the range of 1 × 1012–3 × 1013 cm−2. Complete amorphization was not achieved even at the maximum fluence. The calculated value of the critical fluence was (9.2 ± 0.1) × 1014 cm−2. According to the results of grazing incidence X-ray diffraction (GIXRD), the volume fraction of the amorphous structure increased from 20 to 70% with increasing fluence from 1 × 1012 up to 3 × 1013 cm−2. The intensity of the 200 YPO4:Gd XRD peak reached ~80% of the initial intensity after recovery annealing (700 °C, 18 h). [ABSTRACT FROM AUTHOR]

A new method for creating nanomaterials based on gallium oxide by ion-beam synthesis of nanocrystals of this compound in a SiO2/Si dielectric matrix has been proposed. The influence of the order of irradiation with ions of phase-forming elements (gallium and oxygen) on the chemical composition of implanted layers is reported. The separation of gallium profiles in the elemental and oxidized states is shown, even in the absence of post-implantation annealing. As a result of annealing, blue photoluminescence, associated with the recombination of donor–acceptor pairs (DAP) in Ga2O3 nanocrystals, appears in the spectrum. The structural characterization by transmission electron microscopy confirms the formation of β-Ga2O3 nanocrystals. The obtained results open up the possibility of using nanocrystalline gallium oxide inclusions in traditional CMOS technology. [ABSTRACT FROM AUTHOR]

The conditions for the growth of polycrystalline GeSn layers on diamond substrates are determined. The effect of the incorporation of Sn in Ge layers on their morphology, structure, and transport properties is studied. GeSn layers with a thickness of 0.5 μm, obtained by the hot‐wire chemical vapor deposition method at 300 °C without annealing, are uniform with a surface roughness of less than 1.0 nm. It is shown that the incorporation of 1% Sn into the Ge lattice makes it possible to significantly increase the hole mobility of the GeSn layers from 30 to 140 cm2 V−1 s−1 despite the small crystallite grain size of 35–45 nm. [ABSTRACT FROM AUTHOR]