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The processes of formation of a thin film of cobalt disilicide on the silicon surface due to the formation of several nuclei of atomic thickness on the surface of the silicon substrate are presented. To create these structures, the ion implantation method was used. The dependence of the depth of penetration of ions into the substrate during ion implantation on temperature and ion dose was determined. In the case of implantation of Co+ ions into Si at room temperature silicon uniformly combines with Co atoms at a depth of 3.5–4 nm, the Co concentration in these layers is 45–50 at. %. Co has been shown to form chemical bonds with Si atoms in the sample containing 40–45 atomic % of Co. When implanting Co+ into Si at 600 K, it was found that the depth of the same added layer is 2.5–3 nm, and CCo forming bonds with Si atoms increases to 85–90%. [ABSTRACT FROM AUTHOR]

The processes of formation of a thin film of cobalt disilicide on the silicon surface due to the formation of several nuclei of atomic thickness on the surface of the silicon substrate are presented. To create these structures, the ion implantation method was used. The dependence of the depth of penetration of ions into the substrate during ion implantation on temperature and ion dose was determined. In the case of implantation of Co+ ions into Si at room temperature silicon uniformly combines with Co atoms at a depth of 3.5–4 nm, the Co concentration in these layers is 45–50 at. %. Co has been shown to form chemical bonds with Si atoms in the sample containing 40–45 atomic % of Co. When implanting Co+ into Si at 600 K, it was found that the depth of the same added layer is 2.5–3 nm, and CCo forming bonds with Si atoms increases to 85–90%. [ABSTRACT FROM AUTHOR]

The processes of formation of a thin film of cobalt disilicide on the silicon surface due to the formation of several nuclei of atomic thickness on the surface of the silicon substrate are presented. To create these structures, the ion implantation method was used. The dependence of the depth of penetration of ions into the substrate during ion implantation on temperature and ion dose was determined. In the case of implantation of Co+ ions into Si at room temperature silicon uniformly combines with Co atoms at a depth of 3.5–4 nm, the Co concentration in these layers is 45–50 at. %. Co has been shown to form chemical bonds with Si atoms in the sample containing 40–45 atomic % of Co. When implanting Co+ into Si at 600 K, it was found that the depth of the same added layer is 2.5–3 nm, and CCo forming bonds with Si atoms increases to 85–90%. [ABSTRACT FROM AUTHOR]

Thin films of CrSi2 of various thicknesses, deposited on the Si(111) surface using magnetron sputtering, have been examined through a combination of electron spectroscopy and microscopy techniques. In this article, the mechanism of film formation by sputtering in very short times by the method of magnetron sputtering was studied. In addition, the electrophysical and thermoelectric properties of the formed film were studied for the first time in the article. For the first time, the composition, surface morphology, and cross-section of the thin films, as well as the temperature dependences of the resistivity, Seebeck coefficient, and power factor have been investigated. In the article, a SiO2 substrate on the Si(111) surface was used to form a CrSi2 film. This substrate was chosen due to its temperature resistance and good dielectric properties. The following articles provide information on weekubstrates for growing structures, their formation, and thermoelectric properties (Noroozi et al. in ECS J Solid State Sci, 6:Q114, 2017; Muhammad et al. in Chem Papers, 77:6533–6542, 2023; Alhadhrami et al. in J Taibah Univ Sci, 17:2236368, 2023). It is proven that an amorphous CrSi2 film entirely covers the SiO2/Si(111) surface, starting at a thickness of ~ 400 Å (deposition time ~ 60 s). A homogeneous polycrystalline CrSi2/SiO2/Si(111) film is created after heating the CrSi2/SiO2/Si(111) system to a temperature of approximately 750 K. It is demonstrated that for a CrSi2/SiO2/Si(111) film with varying thicknesses (80 and 180 nm), the resistivity ρ, the power factor P, and the Seebeck coefficient S change nonlinearly with increasing temperature. For CrSi2 films with varying thicknesses, their values are marginally different from one another. In particular, it was found that with increasing T, the resistivity ρ of the polycrystalline film decreases, while the Seebeck coefficient S increases. It is demonstrated that the excitation of electrons from hybridized 3p levels of Si and 4 s and 3d levels of Cr results in three peaks in the photoelectron spectrum. [ABSTRACT FROM AUTHOR]

4-probe measurements of surface resistivity, measurements of dark and light current-voltage characteristics, the possibilities of using a thin PdSi film to obtain perfect nano-sized ohmic contacts on the Si(111) surface have been investigated using Auger electron spectroscopy methods in combination with ion etching of the surface. It has been shown that the depth of Ni diffusion in the Ni-Si (111) system is 400 - 500 Å at indoor temperature, and 70 – 80 Å in the Ni-PdSi-Si (111) system. The quality of the ohmic contact in the latter case does not change up to T = 800 K and withstands luminous flux illumination up to F = 1100 lux. It is shown that the resistivity of the PdSi film passes through a minimum at T = 900 – 1000 K. An analysis of the results obtained will be given in the article. [ABSTRACT FROM AUTHOR]

Using the methods of secondary ion mass spectrometry, elastic peak electron spectroscopy, and Auger electron spectroscopy, the elemental and chemical composition of the surface and concentration profiles of the distribution of atoms over the depth of silicon implanted with ions with energy E0 = 1 keV at a dose of D = 6 × 1016 cm–2 were studied. It was found that oxides and suboxides of Si (SiO2, Si2O, and SiO0.5) were formed in the ion-doped layer, which also contained unbound O and Si atoms. Post-implantation annealing at 850–900 K led to the formation of a stoichiometric SiO2 layer ~25–30 Å thick. [ABSTRACT FROM AUTHOR]

A method of low-energy ion implantation is used for the first time to create oxide layers on the surface of a CdS material. After annealing at a temperature of 800 K of CdS implanted with ions with an energy of E0 = 1 keV at a dose of Dsat ≈ 8 × 1016 cm–2, a three-component film of CdO0.7S0.3 is formed, and after annealing at 900 K a CdO film is formed. Using Auger-electron spectroscopy, photoelectron spectroscopy, and light-absorption spectroscopy, the composition, parameters of the energy bands, optical parameters, and densities of state of valence electrons of CdO0.7S0.3 and CdO nanofilms are determined. The results of the study allow one to consider the possibility of using CdO0.7S0.3 films as transparent films and contact layers in various devices including solar cells. [ABSTRACT FROM AUTHOR]

The paper reports the results of study of composition, emission, and optical properties of polycrystalline W and Mo samples implanted with Ba+ ions and coated with submonolayer Ba atoms by applying Auger electron spectroscopy, secondary electron emission coefficient σ technique, as well as the photoelectron quantum yield Y. The experimental part was carried out by using the instrumentation and under vacuum Р ≈ 10-6 Pa. It is shown that during the implantation of Ba ions in the surface layers of refractory metals, a mechanical mixture of the W + Ba and Mo-Ba types is formed. It has been established that the values of the coefficient of secondary electron emission σ and the quantum yield of photoelectrons Y at the same value of the work function еφ in the case of implantation of Ba+ ions are much larger than in the case of deposition of atoms. The obtained experimental results are substantiated by theoretical calculations. [ABSTRACT FROM AUTHOR]

Using the methods of Auger electron spectroscopy, scanning electron microscopy, and measuring the angular dependences of the coefficient of inelastically reflected electrons, changes in the morphology, composition, and structure of CaF2 surface layers under electron bombardment with an energy of Ee = 1–8 keV are studied. The composition of the CaF2 surface changes noticeably at Ee = 2–3 keV and an electron dose of D ≥ 1018 cm–2. It is found that at a dose of less than 1018 cm–2, electrons are incident on separate sections of the CaF2 film. As D increases, the sizes of these sections increase, and starting from D = 8 × 1018 cm–2, the boundaries of neighboring sections overlap. The surface is completely covered with Ca atoms. After annealing at 900 K, a single-crystal Ca film is formed. At Ee = 3 keV, the thickness of the Ca film is ~25–30 Å. [ABSTRACT FROM AUTHOR]

The composition, structure, and optical parameters of a SrF2(111) single-crystal sample with a surface Ge nanofilm are studied using Auger-electron spectroscopy (in combination with surface etching with Ar+ ions and measuring the angular dependences of the coefficient of inelastic electron reflection η) and light-absorption spectroscopy. It is shown for the first time that preliminary bombardment of the SrF2 surface with Ar+ ions with E0 = 1 keV at T = 750 K makes it possible to obtain homogeneous epitaxial Ge nanofilms starting from a thickness of 30 Å. It is assumed that the transition layer formed at the Ge–SrF2 interface also has a cubic lattice with a parameter close to the lattice constants of Ge and SrF2. [ABSTRACT FROM AUTHOR]

The regularities of the formation of thin Mn/Si (111) nanofilms during solid-phase deposition of Mn on Si under conditions of ultrahigh vacuum (P = 1 0 − 7 Pa) and thin Mn4Si7/Si (111) nanofilms during annealing of the Mn/Si system have been studied. It has been established that silicon atoms diffuse into the Mn film up to a thickness of Θ = 1 0 –12 monolayers, and Mn in Si up to Θ = 8 –10 monolayers, therefore, a transition layer of nonstoichiometric MnxSiy silicide is formed at the Mn–Si interface. After heating at T = 1 0 5 0 K, the higher manganese silicide (HMS) Mn4Si7 is formed. In particular, it was found that the bandgap of Mn4Si7is E g ≈ 0. 7 2 eV, and the electron affinity is χ ≈ 3 eV and in the work, the optimal thermal diffusion conditions for the formation of stoichiometric Mn4Si7 silicide are determined. It is shown that at T ≤ 1 0 0 0 K, a partial formation of a chemical bond between manganese and silicon atoms occurs. At 1100 K, a thin Mn4Si7 film with a good stoichiometric composition is formed. [ABSTRACT FROM AUTHOR]

Under the same experimental conditions, the processes of adsorption and the heterogenous reaction of dissociation on the surface and thermal desorption of C17H19NO3 morphine molecules with m/z 285 amu on the surface of oxidized tungsten are studied by the nonstationary surface ionization, such as the voltage modulation and flux modulation methods. The experiments are carried out using a high-vacuum mass spectrometer, in which a "black chamber" is used, all walls of which are cooled with liquid nitrogen. The kinetic characteristics of the processes of thermal desorption and the heterogeneous reaction of the dissociation of molecules on the surface, such as the rate constant of thermal desorption in the ionic and neutral states K+ and K0, the corresponding activation energies of thermal desorption E+ and E0, the pre-exponential factors C and D, as well as the rate constant of the heterogeneous dissociation reaction K d and the activation energy of heterogeneous reaction of dissociation on the surface, exponential factors in the equation of continuity of the surface concentration for C9H7N+CH3 radicals with m/z 144 amu during the adsorption of morphine molecules on the surface of oxidized tungsten are determined. [ABSTRACT FROM AUTHOR]