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Information × Registration Number 0201U005577, 0101U000716 , R & D reports Title Quality improvement of sollar cells based on monocrystalline silicon and wide-band AIIBVI compounds popup.stage_title Head Gorlej Petro Mykolajovych, Registration Date 10-08-2001 Organization Yuri Fedkovych Chernivtsi National University popup.description2 Researches of structural changes in subsurface layers of Si single crystals during formation amorphous layers hidden under the surface are carried out. It is established, that phosphorous ion (with 180 keV energy and doze of the order 10^15 ion/cm2) implantation and subsequent short-term temperature annealing at T=500°C cause essential structural changes in subsurface areas of silicon. The great strains in direction perpendicular to interface characterise the structures formed in such way. In the given paper the model of defect formation in silicon under light ion implantation is proposed which describes the whole complex of available experimental results qualitatively, and in a number of cases well enough quantitatively. In contrast to the models existing by now, it takes into account the dissociation processes of complex defects. In the frame of assumption about subsurface vacancy absorption layer existence the expressions for spatial distributions of secondary defect stationary concentrations are o btained with the aid of Lie group theory. Non-stationary complex defect system behavior in silicon is simulated depending on vacancy trap concentration, ion current density and implanted atom energy. The results of investigations of evolution equations' system describing hydrogen passivation of silicon are presented. Using Lie group theory the explicit form of infinitesimal operators admitted by the system under constant hydrogen atoms diffusivity in the sample is determined. Invariant solutions' classification and given system's reduction to the systems of ODEs are carried out. Possibility of analytical solution of passivation problem is shown. In the ranges of carriers separation mechanism by spatial inhomogeneities long-range relaxation (LR) phenomenon of photocurrent kinetics in compensated samples Si<B,S> and Si<B,Rh> is discussed. Mathematical model of complexes (divacancies) formation and dissociation is examined. It explains the processes in semiconductor under irradiation. Stable regimes of the give n model are studied and partial exact solution of the problem for time change of divacancy concentration is obtained. Dependencies of LR process time constant on irradiation dose are calculated. Possibility of photocurrent relaxation kinetics prediction for irradiated materials is proven on the basis of results obtained. Integral and spectral characteristics of photosensitive structures of metal-CdTe have been investigated. It has been determined that the preceding annealing of basis substrates in air under certain conditions leads to the essential improvement of photoconverter parameters. Solar cells with efficiency 13 % (300 K, AM2) were made on the base of surface-barrier diods. Thin polycrystalline CuInS2 films were obtained by spraying with further pyrolysis and their transmittency were investigated depending on technological conditions. It was shown that parameters of the films grown at the room temperature (concentration and drift mobility of main carriers, band gap, spectral dependence of absorption coefficient with energy from 1,42eV to 1,58eV) are in good correlation with the published data. Product Description popup.authors popup.nrat_date 2020-04-02 Close