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Registration Number

0214U002107, 0113U000388 , 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 4 "Working-out of the technology for fabrication of macroporous silicon structures with optimum thickness SiO2 nanocoating and nanoparticles ZnO and CdS"

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Head

Karachevtseva Liudmyla,

Registration Date

17-01-2014

Organization

Institute of Semiconductor Physics of National Academy of Sciences of Ukrain

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The scientific and technical concept of Stage 4 is that for the manufacture of efficient light-emitting elements based on macroporous silicon structures with nanoparticles proposed structure with optimum thickness SiO2 nanocoating and ZnO or CdS nanoparticles. Based on this, an important task is working out a method of dry oxidation of macroporous silicon structures for SiO2 layer thickness of 5 nm to 30 nm; definition of the local electric field intensity at the interface "silicon matrix - SiO2 - layer of nanoparticles ZnO or CdS" by IR absorption; measurement of photoluminescence macroporous silicon structures with optimum thickness nanocoating SiO2 and nanoparticles CdS; develop a model of the photoluminescence of CdS nanoparticles on macroporous silicon structures with nano SiO2. In accordance with the main objective stages: (1) determined the effect of cleaning the surface of structures by their oxidation and oxide etching to reduce the concentration of nonradiative recombination centers; (2) determined intensity of the electric field at the Si-SiO2 interface and the dependence of the electron scattering time versus energy t~ E3/2, corresponding to the scattering by ionized impurities; (3) in the IR absorption spectra of oxidized macroporous silicon structures with nanoparticles observed formation TO and LO phonon peaks and additional peaks associated with surface multiphonon polaritons; and (4) the electric field intensity is maximum (6.8·104 V/cm) for purified by oxidation and ultrasonic treatment macroporous silicon structures with a thickness of 10 nm oxide and nanocoating of CdS nanoparticles 25 nm thick, which received the maximum photoluminescence intensity, (5) the photoluminescence quantum efficiency increases with the flow of electrons, their residence time on the interface of Si-SiO2 and due to the evaporation of water molecules from the layer of CdS in PEI, (6) for the oxidized macroporous silicon structures with nanocoating of CdS intensity and position of photoluminescence bands determined by the processes of the exciton radiative recombination via surface states of quantum dots, which interact with both the environment polymer and the boundary "CdS - SiO2/Si".

Product Description

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Карачевцева Людмила Анатоліївна
Кучмій Степан Ярославович

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2020-04-02