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Information × Registration Number 0214U008216, 0114U003538 , R & D reports Title The development of nanotechnology ZnO and CdS nanoparticles synthesis for manufacturing of light-emitting elements based on macroporous silicon structures with nanocoatings, stage 5 "The development of light-emitting elements based on macroporous silicon structures with SiO2 nanocoating and ZnO and CdS nanoparticles." popup.stage_title Head Karachevtseva Liudmyla, Registration Date 12-12-2014 Organization Institute of Semiconductor Physics of National Academy of Sciences of Ukrain popup.description2 The scientific and technical concept of the project is that for the manufacture of efficient light-emitting elements based on macroporous silicon structures with nanocoatings proposed structure with optimum depth of macropores and thickness of SiO2 nanocoating and light emitting layer of ZnO and CdS nanoparticles. In accordance with the main goal determined the influence of the surface structures cleaning by their oxidation and etching the oxide at reducing the concentration of nonradiative recombination centers. It was found that the dependence of the surface electrons scattering time from the energy ~E3/2 corresponds to the scattering by ionized impurities. In the IR absorption spectra of oxidized macroporous silicon structures with nanoparticles observed the formation of TO and LO phonon peaks and additional peaks associated with surface multiphonon polaritons. Get the high photoluminescence intensity due to an increase flow of electrons from the silicon matrix towards the nanocrystals layer in conditions of maximum electric field intensity at the silicon-silicon oxide boundary which reaches 6.8·10 4 V/cm for purified by the oxidation and ultrasonic treatment macroporous silicon structures with oxide thickness of 10 nm and nanocoating of CdS nanoparticles thickness of 30 nm. The photoluminescence quantum yield of the nanoparticles increases during the first two weeks due to the evaporation of water molecules and reaches 28%. The intensity and position of the photoluminescence bands determined by the processes of radiative recombination of excitons through the surface states of quantum dots as interacting with the polymer environment, and to the border "CdS - SiO2 / Si". The developed technology allows simultaneously increase the photoluminescence quantum yield, enhance the strength of structures and protect the surface from degradation. The obtained results will allow to make an effective light-emitting structures based on nanocrystals on the surface of macroporous silicon for hubs and sources of "white" light, completely inorganic multi-color LEDs for silicon micro- and nanophotonics. Product Description popup.authors Карачевцева Людмила Анатоліївна Кучмій Степан Ярославович popup.nrat_date 2020-04-02 Close