The results of measuring the charge-discharge characteristics of solid-state thin-film lithium-ion batteries with a nanocomposite anode based on a-Si(Al) solid solution are presented. The charging characteristics of batteries have a feature in the form of a step on the smooth branch of the charge curve. It is shown that the appearance of the step is associated with the compensation of a-Si(Al) and the change from hole to electron conductivity due to lithiation of the electrode during charging. As a result of lithiation, the electron over-barrier current becomes the main component of the charging current. To maintain a galvanostatic charge mode, the potentiostat increases the voltage by the height of the potential barrier, which leads to the appearance of a step on the charging curve. The impedance of a solid-state thin-film lithium-ion battery of the LiCoO2–LiPON–Si@O@Al electrochemical system was measured in the temperature range from –20 to 50°C. A structural model of the accumulator is proposed and the parameters of the structural elements of the model are calculated which provide the best fit for experimental Nyquist diagrams. The obtained values of the electrodes’ resistivity are orders of magnitude higher than the results of direct measurements and data from literary sources. According to the IV-characteristics obtained by cyclic voltammetry the high resistance of the electrodes is due to the metal-semiconductor contact and the varistor effect of the electrode material. The results obtained make significant adjustments to the interpretation of the impedance spectra and structural models of solid-state lithium-ion batteries based on semiconductor materials.

The purpose of this work is to study the characteristics of the junction between the titanium down conductor of a thin-film solid-state lithium-ion battery (a-Si) and a negative Si@O@Al nanocomposite electrode. The results of measuring the band gap of the Si@O@Al nanocomposite and the height of the Schottky barrier of the Ti–Si@O@Al junction are presented. The transmission and reflection spectra of Si@O@Al films and its main phases a-Si, a-SiOx, and a-Si(Alx) are studied. The band gap of Si@O@Al was determined by the Tauc method, which is 1.52 eV for a-Si and 1.15 eV for nc-Si. The IV characteristics of Ti‒Si@O@Al, Ti–a-Si, Ti–a-SiO0.8, and Ti–a-Si0.9(Al0.1) structures have been studied and the height of the Schottky barrier has been determined. The results obtained make it possible to estimate the Fermi energy of the nanocomposite and to interpret the hike in the SSLIB charging voltage as a result of the Al acceptor impurity compensation during lithiation. A change in the majority charge carriers in Si@O@Al leads to a decrease in the hole current and an increase in the density of the over-barrier electron current, as a result of which a step with a height of 1.5 V is formed on the charging curve.

We investigate the processes of microrelief formation on a Si(100) surface under irradiation with a Ga+-ion beam with an energy of 30 keV and a fluence of D = 1.25 × 1018–2 × 1019 cm–2 at incident angles of θ = 30°–85°. Within the angular range of θ = 40°–70°, a faceted wavy relief forms on the Si surface, while at θ = 30°, a sinusoidal relief develops. An experimental dependence of the periodic structure wavelength as a function of irradiation time λ(t) t n, where n = 0.33–0.35, is obtained. The average values of relief propagation velocities and their direction relative to the incident ion direction are determined for θ = 30° and 40°, amounting to –5.3 ± 0.6 and –6.3 ± 0.6 nm s–1, respectively. The results are discussed in detail within the framework of existing models of wavelike surface relief formation under ion bombardment.

The design of a laboratory solid-state thermostat based on Peltier elements with an operating temperature range from −50 to +90°C is described. The thermostat is made from up-to-date circuitry components. Thin films, silicon chip fragments with analyzed structures, and other miniature objects with lateral dimensions of up to 15 × 15 mm can be used as a test sample. The sample thickness is limited by the thermal conductivity of its material, and it can be as large as 3 mm.

The results of measuring the charge-discharge characteristics of solid-state thin-film lithium-ion batteries with a nanocomposite anode based on a-Si(Al) solid solution are presented. The charging characteristics of batteries have a feature in the form of a step on the smooth branch of the charge curve. It is shown that the appearance of the step is associated with the compensation of a-Si(Al) and the change from hole to electron conductivity due to lithiation of the electrode during charging. As a result of lithiation, the electron over-barrier current becomes the main component of the charging current. To maintain a galvanostatic charge mode, the potentiostat increases the voltage by the height of the potential barrier, which leads to the appearance of a step on the charging curve. The impedance of a solid-state thin-film lithium-ion battery of the LiCoO2-LiPON-Si@O@Al electrochemical system was measured in the temperature range from -20°С to 50°С. A structural model of the accumulator is proposed and the parameters of the structural elements of the model are calculated which provide the best fit for experimental Nyquist diagrams. The obtained values of the electrodes’ resistivity are orders of magnitude higher than the results of direct measurements and data from literary sources. According to the IV-characteristics obtained by cyclic voltammetry the high resistance of the electrodes is due to the metal-semiconductor contact and the varistor effect of the electrode material. The results obtained make significant adjustments to the interpretation of the impedance spectra and structural models of solid-state lithium-ion batteries based on semiconductor materials

Experimental studies of the germanium surface morphology development under irradiation with a focused gallium ion beam at different angles of incidence and fluences are presented. It is shown that a nanoporous structure formes in the near-surface layer starting with a dose of 5.10(15) cm(-2).This leads to the formation of a sponge- like morphology with a wall thickness of about 20 nm and a depth up to 150 nm with an increasing dose. Changing the ion beam incidence angle with respect to the surface normal leads to a tilt of the pores walls in the collinear direction.

The results of measuring the charge-discharge characteristics of solid-state thin-film lithium-ion batteries with a nanocomposite anode based on a-Si(Al) solid solution are presented. The charging characteristics of batteries have a feature in the form of a step on the gentle branch of the curve. It has been suggested and substantiated that the appearance of the step is related to the gradual compensation and change of the a-Si(Al) hole conductivity to electronic one as the lithium concentration increases. As a result, the a-Si(Al)|Ti ohmic contact becomes rectifying, and the electrons participating in the Faraday process are forced to overcome the Schottky barrier. The potential growth required to maintain the galvanostatic charge regime appears as a step on the charge curve.

masha_19957@mail.ru Abstract. Influence of the initial Si surface state on the rate of ripple nucleation under bom-bardment with low-energy O2+ ions was investigated. It was found that the creation of a defect area in the Si near-surface layer or the creation of the initial surface relief by ion bombardment with a focused Ga+ ion beam facilitates a significant acceleration of the ripple nucleation on the Si surface during subsequent irradiation with an O2+ ion beam.

The silicon surface was irradiated with 30 keV gallium ion beam at incidence angles from 0 to 50 and fluences from 6middot10(16) to 5middot10(18) cm(-2). Surface topography was investigated by scanning electron microscopy. It was found that one of four types of a relief can be formed on the silicon surface depending on the ion beam incidence angle and these fluences. Pattern formation starts with fluences of ~2middot10(17 )cm(-2). The peculiarities of a relief evolution can be explained by the angular dependences of silicon sputtering with gallium ion beam and the possible existence of implanted gallium in the near-surface layer in the form of precipitates.

The processes of microrelief formation on the Si(100) surface under irradiation with a 30-keV Ga+-ion beam with doses of D = 6 × 1016–4 × 1018 cm–2 at incidence angles of θ = 0°–50° are studied. It is established that a ripple structure is formed in an angular range of θ = 25°–35° at D = 2 × 1017–2 × 1018 cm–2. However, a well reproducible ripple structure is observed at incidence angles of θ = 30° ± 2° starting from irradiation doses of 2 × 1017 cm–2. As D increases from 2 × 1017 to 2 × 1018 cm–2, the wavelength and the amplitude increase from ~150 to ~400 nm and from ~30 to ~70 nm, respectively. At D > 2 × 1018 cm–2, the ripple structure is destroyed. The features of the formation of such a Si surface relief using a Ga+-ion beam are a rather narrow angular range in which the relief is formed and the value of the irradiation dose at which its nucleation begins. The reasons for these features can be precipitates of implanted Ga in the Si surface layer and the angular dependences of the sputtering yield and composition of the Si surface layer irradiated with a Ga+ ion beam.

The results on measuring the I-V characteristics of the metal-semiconductor transition within the Ti(200nm)|Si@O@Al(179nm)|Ti(203nm) test structure are presented. The basis of the Si@O@Al nanocomposite is a solid solution of Al in amorphous silicon a-Si(Al). The I–V of the test structure has a form characteristic of a reverse-biased ohmic contact between a metal and a p-type semiconductor, which implies that a-Si(Al) is a substitutional solid solution. It is shown that the I-V fits well the framework of the metal-semiconductor transition model and the varistor effect of the nanocomposite. Within the framework of the percolation model, it is shown that the I–V give values of the Si@O@Al resistivity, which are overestimated with respect to the resistance of the a-Si(Al) solid solution.

The results of measuring the charge-discharge characteristics of solid-state thin-film lithium-ion batteries with a nanocomposite anode based on the a-Si(Al) solid solution are presented. The charging characteristics of batteries have a feature in the form of a step on the gentle branch of the U(t) curve. It has been suggested and substantiated that the appearance of the step is related to the gradual compensation and change of the a-Si(Al) hole conductivity to electronic one as the lithium concentration increases. As a result, the a-Si(Al)|Ti ohmic contact becomes rectifying, and the electrons participating in the Faraday process have to overcome the Schottky barrier. The potential growth required to maintain the galvanostatic charge regime manifests itself as a step on the charge curve. Keywords: thin film solid-state lithium-ion battery, amorphous silicon, solid solution, sp 3 hybridization, lithiation, Schottky barrier.

X-ray diffractometry, energy-dispersive X-ray analysis, Raman spectroscopy, and electron microscopy are used to study the chemical, structural, and morphological properties of exfoliated nanographite and nanographite films created via electrophoresis. The defectiveness of exfoliated nanographite is estimated. The obtained data show an increase in the calculated values of the density of defects in exfoliated graphite, compared to that of the initial foil.

The results on measuring the I--V characteristics of the metal-semiconductor transition within the Ti (200 nm)|Si@O@Al (180 nm)|Ti (203 nm) test structure are presented. The basis of the Si@O@Al nanocomposite is a solid solution of Al in amorphous silicon a-Si(Al). The I--V of the test structure has a form characteristic of a reverse-biased ohmic contact between a metal and a p-type semiconductor, which implies that a-Si(Al) is a substitutional solid solution. It is shown that the I--V fits well the framework of the metal-semiconductor transition model and the varistor effect of the nanocomposite. Within the framework of the percolation model, it is shown that the I--V give values of the Si@O@Al resistivity, which are overestimated with respect to the resistance of the a-Si(Al) solid solution. Keywords: nanocomposite, amorphous silicon, solid solution, Schottky barrier, nonlinear conductor, dangling bonds.

The process of microrelief formation on Si (100) surface under 30 keV Ga+ ion beam bombardment with doses 2⋅1017 - 4⋅1018 ion/cm2 at incident angles θ = 0 - 50° was studied. It was found that wave-like structures form on the surface at θ = 25° - 35° and doses 6⋅1017 - 2⋅1018 ion/cm2. The nice ripple formed at θ = 30±2° incident angles and irradiation dose 1018 ion/cm2.

The electrochemical exfoliation of graphite is studied via X-ray diffractometry and Rutherford backscattering spectrometry. It is shown this process allows graphite particles to be obtained with virtually half the normal crystallite size, and thus the number of graphene layers in them. The effect the parameters of exfoliation have on the chemical composition of the resulting graphite particles is established.