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Information × Registration Number 0223U004793, 0123U103363 , R & D reports Title Elaboration of optimal conditions for the synthesis of solid solutions of wide bandgap oxides and monitoring of their structural, electrical and optical characteristics, as well as chemical composition popup.stage_title Head Khomenkova Larysa Yu., Доктор фізико-математичних наук Registration Date 04-12-2023 Organization V. Lashkarev Institute of Semiconductor Physics of National Academy of Sciences of Ukraine popup.description2 Report SRW: 120 p., 3 chapters, 50 figures, 6 tables, 59 references Ceramics and polycrystalline layers of MgxZn1–xO were produced by solid-phase reaction method, and the effect of doping, sintering regimes and compacting pressure (for ceramics) on their structural, (photo)electrical, optical, and luminescence characteristics was elucidated. The mechanisms of the formation of the ceramic solid solution versus the ZnO and MgO content in the charge and their preliminary treatments, as well as compacting pressure, were proposed. Upon ceramics sintering, the simultaneous formation of two crystalline phases of solid solutions - a hexagonal and a cubic structure - occurs. The relative contribution of each phase is determined by the processes of diffusion of Zn ions into cubic MgO grains and Mg ions into hexagonal ZnO grains. The maximal magnesium content in the hexagonal phase of the solid solution is 13 at.%, which expands the band gap of hexagonal MgxZn1–xO up to 3.68 eV. It was established that doping ZnO and MgxZn1–xO with group I acceptors (Li, Cu, Ag, Na) with a content of up to 0.1 аt.% enhances visible photoluminescence of the hexagonal phase. The dependence of the dark conductivity compensation was found on the sintering temperature of ceramics and polycrystalline layers, the concentration and type of the group I acceptor impurity, and the material of the substrate used for layer deposition. Based on the (co)precipitation method, an approach for preparing undoped and doped ZrO2-based powders with a stable tetragonal/cubic structure was developed. It is shown that in Y-ZrO2 powders additionally doped with other impurities during the coprecipitation process, yttrium plays a major role in the stabilization of cubic/tetragonal structure. The reasons for the destabilization of the cubic structure of (Sc,Ce)-ZrO2 were determined. The non-destructive express diagnostics of structural and optical properties of oxide-based ceramics was proposed. Product Description popup.authors Kozoriz Kostyantyn O. Polishchuk Yuliia O Ponomaryov Semen S. popup.nrat_date 2023-12-04 Close