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The tricky optimization procedure of silicon-on-sapphire heteroepitaxy is one of the restricting factors to widespread utilization of the silicon-on-sapphire (SOS) wafers. In order to eliminate the given technological barrier in the work the process of gas-phase forming the silicon initial layer on the sapphire R-plane has been investigated. The parameters of the manufactured layers have been analyzed using the production methods of the quality control as well as by XRD, SEM and Raman spectroscopy. The resistivity profiles of the SOS layers have been obtained by the specific resistance spreading method (SPR). It has been shown that the execution of the initial stage of growing at 910–930 °C results in reduction of the silicon layer autodoping by aluminum from the substrate. The heat treatment of the initial layer, formed at 945–965 °C enables to obtain the SOS structures of high structural quality in a wide temperature range of the main layer deposition 960–1005 °C. A comparison of the SOS structures, obtained at the optimal parameters of the investigated technique and in the standard process has demonstrated a reduction of the full width half maximum of rocking curve to ~0.24, the reduction of mechanical stresses of compression up to 0.8–1.96 GPa, the homogeneity of the specific resistance profile up to 180–350 nm depth. Due to the application of the developed technological techniques the homogeneity of the SOS control parameters within the process significantly has increased, which has enabled to improve the productivity of the manufacturing process.
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The method for molecular quasi-dimensional conductor formation under the alternating electric field based on polianiline molecules and multiwalled carbon nanotubes as conductive electrodes has been suggested. On the basis of the calculations of intermolecular interaction and electric field strength the mechanism of such structure formation, based on building molecular dipole in the strong electric field on the end of the nanotubes, has been suggested. Based on simulation a model, which qualitatively explains possible transport mechanisms in the quasi-one-dimensional structure, has been offered.
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The process of the film oxidation of graphene, containing one and several layers, under the influence of UV irradiation structure in water vapor has been investigated. The regularity has been revealed and the difference in topography variation, as well as in the optical properties of grapheme, having a different number of layers, has been demonstrated. The possibility of the surface functionalization with modification of the energy structure of graphene has been revealed. The differences in the mechanisms of UFO oxidation of monolayer, multilayer and few-layered graphene have been analyzed. The correlation of the topographic defects of the graphene material properties and of the structural defects, observed on Raman scattering of light spectra, has been demonstrated.
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The processes of creating the narrow-spectrum photosensitive structures have been investigated. Two technological approaches based on the J-aggregates of cyanine dyes have been proposed: the electro-kinetic deposition of single J-aggregates in the planar configuration of electrodes and the creation of the multi-layer structures with the photosensitive layer from the film of the cyanine dye J-aggregates and transparent electrode from the conductive carbon nanotube network on the flexible substrate of polyethylene phthalate.
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Using the atomic force microscopy methods the morphology of cell structures, cultivated on films from collagen and chitosan fibers, has been studied. The specific features of the growing cells morphology on a submicron level have been investigated, in particular, it has been shown that the number of the flagella of diameter up to 100 nm of the cells grown on the films from the collagen and hitosan fibers is larger than that one of the control samples, grown on glass substrates.
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