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Information × Registration Number 0223U001013, 0121U111717 , R & D reports Title Quasioptical scale modeling of the influence of radiation-induced localized defects in metals and alloys on the optical ellipsometry data popup.stage_title Head Kolenov Ivan V., Registration Date 24-01-2023 Organization Institute of Electrophysics and Radiation Technologies of the National Academy of Sciences of Ukraine popup.description2 The influence of surface defects, such as localized defects, characteristic of polycrystalline materials subjected to ion sputtering, on optical ellipsometry data was studied. It is shown that ellipsometry is insensitive to localized defects in the shape of a parallelepiped, if its size is comparable to or smaller than the wavelength. Spectral studies have shown that as the size of the defect decreases relative to the wavelength of the probing radiation, ellipsometry becomes less sensitive, although reflectometry is sensitive to it. Pit-type defects (indentations on the surface) were considered. It is shown that if the size of the pit is smaller than the wavelength, ellipsometry does not "see" it. On the other hand, reflectometry clearly shows a decrease in reflectivity compared to a defect-free surface. It was also found that reflectometry is not very sensitive to pit depth. Ellipsometry is more sensitive to pit depth in almost all cases investigated, except when the size of the defect is much smaller than the wavelength. For the first time, a study of the possibility of using subterahertz ellipsometry (operating frequency of f = 0.14 THz) for non-destructive non-contact determination of integral values of thickness, structure and composition of coatings obtained by micro-plasma oxidation (MPO) was carried out. The proposed model adequately describes the structure of MPO coatings at all stages of the technological process. This makes it possible to use ellipsometry for non-destructive non-contact express control of the state of these coatings during production, without resorting to additional more complex analytical methods (XRD, SEM, etc.). Methods of numerical modeling of the formation of defects such as dislocation loops at a slow set of doses and modeling of relief change mechanisms in targets irradiated with concentrated energy flows have been developed. Product Description popup.authors Startsev Oleksandr Anatoliyovich Trotsenko Oleg G popup.nrat_date 2023-01-24 Close