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Information × Registration Number 0222U000622, 0120U000266 , R & D reports Title Synthesis of new diamond-like films and "core-shell" structures under the action of short-term pulsed laser irradiation of nitride-carbon films in a supercritical fluid popup.stage_title Head Pashkevich Yurii G., Доктор фізико-математичних наук Registration Date 14-01-2022 Organization Galkin Donetsk Institute of Physics and Technology of the National Academy of Sciences of Ukraine popup.description2  To optimize the processes of laser annealing the next studies have been performed: 1) the accumulated heating of the sample during femtosecond laser ablation; 2) the dependence of the size of the area of laser ablation on the irradiation power; 3) increase in energy in the pulse without increasing of the accumulated heat of the sample; 4) the effect of the duration of laser pulses on the processes in the sample and the fluid around it. Annealing parameters have been set at which the accumulated heat does not change the state of the sample. The method of equalization of the radiation power density in the cross section of the laser beam is substantiated. The set of parameters (frequency of laser pulses and average power) at which the maximum energy in a pulse can be reached is defined. It is shown that increasing the duration of femtosecond laser pulses allows to increase the energy in the pulse without increasing of the accumulated heat. Measurements of inelastic light scattering spectra from 60 areas of nanocolumn nitride-carbon film that were irradiated in a wide range of "time-power" parameters were performed. It has been shown that laser femtosecond annealing with an intensity below the ablation threshold leads to structural changes in the direction of "amorphous carbon" state with formation of a superhard nitride-carbon phase and with increased number of sp3 bonds and increased nitrogen concentration. Product Description popup.authors Dmytruk Andriy M. Kadan Viktor M Prudnikov Anatolii M popup.nrat_date 2022-03-09 Close