Yarovets I. Features of nanosystems based on chalcogenide semiconductors with natural nanostructured matrices.

The aim of the work is study of nanosystems on the base of chalcogenide semiconductors' surfaces with natural nanostructured matrices. The topography, atomic and electron-energetic structure and also elemetal-phase composition of gallium telluride (GaTe), indium selenides (Іn4Se3, InSe) and their intercalates (AgхIn4Se3, NiхInSe) were studied. NixInSe intercalates are novel materials with system of flat nanostructures formed by magnetic impurities, placed in Van der Waals gaps of layered crystal. Structural studies of NixInSe hybrid system allow to conclude about intercalate placement in interlayer gaps only. It was established that cleavage surfaces of GaTe layered crystals are locally in nanosize reconstructed from base hexagonal to monoclinic structure, that is connected with considerable amount of surface defects, such as randomly distributed cleavage steps as high as one Te-Ga-Ga-Te layer-packet and, consequently, are not suitable to formation of nanosystems on their base. It was established that (100) cleavage surfaces of In4Se3 have furrowed structure and are structurally stable and are not reconstructed in the wide 77-295 K temperature range, and thus could be applied to creation of surface conductive (In/Au) nanowires, nanocords, nanodots and other low dimensional structures as martrices/templates which are characterized by anisotropy and low conductivity. Debye-Waller factor and Debye temperature were calculated for Іn4Se3 (100) cleavage surface and it is found that the last one differs from the same for the bulk of In4Se3 layered crystal. It was found that formation of low dimensional pyramidal indium structures is realized by Volmer-Weber mechanism until the moment of inhomogeneous film formation by indium nanodots with it further growth by Stranski-Krastanov mechanism. It also was established that nanodots are preferably formed on (100) Іn4Se3 cleavage surfaces with low conductivity, and quasi one dimensional structures - on layered crystal surfaces with high conductivity. It was established lack of reconstruction of (100) cleavage surfaces intentionally silver intercalated AgхIn4Se3 layered crystals, which show good correlation of surface and bulk lattice parameters and inhomogeneous distribution of intercalate in nanosize (finely dispersed silver clusters) on cleavage surface of AgхIn4Se3 layered crystal.