Babych B. Optically selective elements based on nanocomposite structures

The dissertation is devoted to the development of optically selective elements with given spectral characteristics on the basis of nanocomposite structures taking into account the peculiarities of the microstructure and optical characteristics of nanosized components. The complex researches of spectral dependences of optical parameters of nanosized components and composite structures on their basis are carried out in the work. In the work for the first time the following results were obtained: ‒ The optical parameters of nanosized silver layers were determined on the basis of the results of spectrophotometric studies of experimental silver samples on SiO2 substrates manufactured by vacuum deposition. Approximation dependences of real and imaginary parts of complex dielectric constant of nanosized silver films with thicknesses from 1 to 35 nm in the spectral wavelength range λ = 0.3 ÷ 2 μm are established, which are used as input data of reflective layers of silver in modeling of optically selective elements. ‒ The values of complex effective dielectric constant of nanocomposite layers with metal nanosized chromium phase at values of filling factor 0.15 ÷ 0.54 and materials of dielectric component (Al2O3, SiO2, Cr2O3) are determined. Approximation dependences of complex effective dielectric constant of nanosized composite layers Cr/Al2O3, Cr/SiO2, Cr/Cr2O3 in the spectral range λ = 0.3 ÷ 2 μm are developed, which are necessary for calculation of optical spectral characteristics in the designing selective elements based on nanocomposite structures. ‒ The dependences of the transmission and reflection coefficients of selective elements on the structural parameters of composite layers based on nanosized chromium inclusions have been studied. The spectral shift of the values of the critical wavelength of electromagnetic radiation by 0.4 μm when changing the structural parameters of nanosized components is shown, which allows to control the profile of the spectral dependence of optically selective elements. ‒ Optically selective elements transparent in the visible range of the spectrum which differ from the known analogues in that instead of multilayer dielectric structures is used metal-dielectric composite are proposed. It is shown that the proposed elements on the basis of such structures are marked by the possibility of providing a given optical selectivity. The obtained results can be used to solve the problems covered in the work related to the development of optically selective elements based on nanocomposite structures. Results of dissertation work are used in the educational process of the Microelectronics department of the National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute", namely used in lectures and practical classes in the disciplines "Solid state electronics", "Technology of semiconductor devices and integrated circuits", "Elemental and structural analysis", as well as during the qualification works of students of the department.