The effect of ion-plasma treatment on the physical properties of the surface of GaTe crystals is investigated. Gallium telluride crystals were grown by vertical zone melting under the pressure of an inert argon gas of 10.0 MPa at a temperature of 1000 °C and a zone displacement velocity of 9 mm/hr. The treatment was carried out in argon plasma in a high-density low-pressure radio frequency (RF) inductively coupled plasma reactor at an argon ion energy of 100-200 eV for 15-120 s. Using scanning electron microscopy methods, it was shown that the formation of nano- and submicron structures of various architectures (nanohillocks, nanocones, droplet structures) occurred on the surface during processing. It is shown that the sputtering processes are accompanied by enrichment of the near-surface layer with metal atoms and a decrease in oxygen content. The formation of nano- and submicron gallium droplets on the surface has been proved by X-ray diffractometry. The analysis of the raman scattering spectra showed a decrease in the oxide phases of tellurium after plasma treatment. It is established that modification of the GaTe surface leads to suppression of specular optical reflection in the range of 0.4-6.2 eV.
Thin Co films on inclined Si(001) substrates were obtained by electron-beam evaporation. It has been established that at angles of incidence of the evaporated material on the substrate of more than 80° (oblique angle deposition), arrays of free-standing Co nanocolumns with a cross section of 25 nm and an aspect ratio (length/transverse size) of at least 15 are formed on the substrate surface. In this case, the magnetic easy axis of the film is oriented along the axis of the nanocolumns, which leads to the appearance of a normal component of the magnetization vector to the film surface. When the substrate rotation is turned on, an array of nanospirals is formed. With a fast rotation of the substrate (30 rpm), the magnetic easy axis approaches the normal to the film surface. At a slow substrate rotation (0.6 pm), an array of nanocoils is formed, imparting pronounced chiral properties to the film.
10-40 nm Ti films with mixed crystalline texture (100)+(001) are exposed to ion bombardment in inductively coupled Ar plasma by applying the bias -30 V to the films. It is found that such a treatment leads to the formation of (100) texture in films. This result is explained by the generation of the compressive stress in films as a result of ion bombardment. The thinner the film the less time is required to form the (100) texture.
Formation of regular arrays of nanorods with high aspect ratio (length to transverse size) has been found in the process of Al thin film growth at oblique angle deposition on silicon substrate by the method of electron beam evaporation. It was found that the optimal conditions for nanostructuring are realized at the inclination angle larger than 80 degrees.
The effect of porosity on the charge-discharge characteristics of thin films based on an Si–O–Al nanocomposite with two types of structure, homogeneous and columnar, is studied. An additional increase in the porosity of thin Si–O–Al films is achieved by removing the $${\text{Si}}{{{\text{O}}}_{x}}$$ phase, where $$1 < x \leqslant 2,$$ when etching in a solution of hydrofluoric acid. The charge-discharge characteristics of the films were investigated in half-cells in the galvanostatic mode. It is shown that processing films with a columnar structure leads to an increase in their specific capacity and stability under extreme charge-discharge modes.
The results of investigation of the polarization relaxation mechanism for the LiPON solid electrolyte by a discharge through an external load are presented. Test cells implemented in the form of encapsulated multilayer structures $${{{{{{\text{Si}{{\text{O}}_{\text{2}}}}/{\text{Pt}}(100\,\,\text{nm})}/{\text{LiPON}\,(1000\,\,\text{nm})}}/{\text{Pt}~(100\,\,\text{nm})}}/{\text{Ti}~(10\,\,\text{nm})}}/{\text{Si}{{\text{O}}_{\text{2}}}}}/{\text{Si}}\;$$ and previously studied by the standard techniques are tested on a special bench measuring discharge characteristics. The core of the method lies in charging the test cell from a stable voltage source up to saturation with the subsequent rapid switch to precision resistance and detection of the voltage drop. The measurements are taken in the load range from 0.1 MΩ to 10 Ω in the temperature range of –50 to 25°C. An equivalent electric circuit for the test cell is proposed, for which a mathematical model of the discharge process is constructed. In the context of the proposed model, the features of the experimental curves are explained by the processes of redox reactions of the lithium ions at the surface of the electrodes and generation of nonequilibrium charge carriers in the bulk upon the charging and discharging of the test cell.
The results of developing the technology of magnetron sputtering deposition of a LiPON solid electrolyte and an experimental investigation of its characteristics are presented. The basic processing operations and parameters providing the formation of films of the proper morphology, structure, and elemental and phase composition are described. The data of the measurement of the physical parameters of the films by cyclic voltammetry and potentiometry are represented.
The results of the experiments on the development of positive thin-film electrodes for lithium-ion accumulators based on vanadium oxides are presented. The deposition modes and controlling methods of the structure and phase composition of the films, diagnostics methods of the structure and phase composition, and the results of the electrochemical tests of the positive electrodes are described.