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Information × Registration Number 0217U003087, 0112U005082 , R & D reports Title Defect formation and kinetic effects in the irradiated and thermally treated semiconductors and nanostructures on their basis popup.stage_title Head Gaidar Galyna Petrivna, Registration Date 17-01-2017 Organization Scientific Center "Institute for Nuclear Research" of National Academy of Sciences of Ukraine popup.description2 It was shown that in the oxygen-containing n-Ge and n-Si samples the anomalous growth of mobility was observed in the range of low doses of gamma-quanta (10^6 - 10^7 R). A model is proposed which explains the features of changes in the charge carrier mobility with increase of irradiation dose and is based on the partial neutralization of scattering center charges by those of the radiation defects produced by irradiation mainly around the scattering centers. The annealing of the main radiation defects in silicon (A-centers, E-centers, divacancies, etc.) was theoretically described based on the experimental data obtained by many authors. The parameters, characterizing this process (the activation energies and the frequency factors), have been determined and the various mechanisms and reactions, which set conditions for annealing of defects, were also proposed. The radius of capture of the mobile radiation defects (vacancy, interstitial carbon, divacancy) by the interstitial oxygen was determined. This radius was located in the ranges from 3 to 4 of the silicon lattice constants. It was found that germanium in silicon is the recombination center for Frenkel pairs, which suppresses the introduction of deep defects of the vacancy type and promotes to increasing of the radiation resistance of the material by about an order. It was revealed that the spectral distribution of the photoluminescence intensity of GaP crystals, grown from the solution-melt, at 4 K comprises two series of lines, caused by the excitons bound on the nitrogen atoms with their phonon replications and lines of donor-acceptor pairs. It was shown that the exciton luminescence is in many times more sensitive to the presence of radiation defects in the sample, than the donor-acceptor radiation. It was found that at low annealing temperatures the clusters of point defects with an average size of 40 - 65 angstrom play a major role in the process of long-term relaxation of conduction of the gallium phosphide irradiated by electrons with 1 MeV energy. It was found that increasing of the annealing temperature leads to the decrease in concentration of the small size defects and volume of large defects due to annealing of their peripheral pieces. It was shown that annealing of defects responsible for the relaxation phenomena, ends at 300 ^оС, and the almost complete recovery of the conduction of sample occurs at 500 ^оС. It was found that the irradiation of silicon by the high-energy particles leads to nanostructurization and changes of its optical constants, as well as to an increase in surface roughness. It is shown that the destruction of subsurface Si layer, caused, probably, by accumulation of vacancy defects, was observed after proton irradiation by fluence 10^16 cm^-2. The irradiation of Si surface by alpha-particles leads to the compaction of the surface layer. It was shown the prospect of modifying of the Si surface by the charged nuclear particles for the gas sensor systems based on nanosilicon structures. The optimum technological conditions for obtaining from the gaseous phase the Si(sub 1-x)Ge(sub x) whiskers with х = 0.01 - 0.08 and transverse dimensions of 0.1 - 80 мкм were defined. It was found that the samples of Si(sub 1-x)Ge(sub x) solid solution with composition of х = 0.03 is the most homogeneous on distribution of germanium and are characterized by the maximum value of microhardness. The formation of periodic structure in the form of heavily damaged layers containing voids (pores) and perpendicular to the flow of ions was revealed both in the area of ion path and behind it under irradiation of silicon crystals by alpha-particles (helium ion) with the energy of 27.2 MeV and the beam currents in the range from 0.25 to 0.45 microampere. The damaged layers were observed only in the range of ion path when the beam current increases approximately to 1 microampere. The dependence of number of layers in range of the ion path from the beam intensity was established. The formation of ordered structures and spread them in the region behind the ion path was explained by the concept of mobile solitons, which propagate in the crystal along the densely packed directions. A complex research of the surface and bulk properties of the high-resistance silicon in order to solve the problem of the creating of spectrometric semiconductor detectors with predetermined parameters was carried out. The method of accelerated formation of surface-barrier structures through applying a reverse voltage at the stage of the forming of potential barrier in the aurum-silicon contact was proposed. It was found that after the deposition of aurum on the silicon surface the optimal formation of qualitative and stable surface-barrier p-n-junctions occurs with aging of structures in an atmosphere of the moist oxygen. Product Description popup.authors Анохін Ігор Євгенович Барабаш Людмила Іванівна Верцімаха Ганна Віталіївна Гайдар Галина Петрівна Зінець Олег Сергійович Кібкало Тетяна Іванівна Карпенко Андрій Якович Ластовецький Володимир Францевич Литовченко Михайло Вадимович Литовченко Петро Григорович Макуха Олександр Миколайович Полівцев Леонід Андрійович Старчик Маргарита Іванівна Сугаков Володимир Йосипович Тартачник Володимир Петрович popup.nrat_date 2020-04-02 Close