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Information × Registration Number 0217U002074, 0116U006696 , R & D reports Title Photo-thermo-acoustic conversion in inhomogeneous structures based on silicon under laser irradiation popup.stage_title Head Burbelo Roman, Доктор фізико-математичних наук Registration Date 17-01-2017 Organization Taras Shevchenko Kiev University popup.description2 The object of study - Photo- thermo- acoustic conversion into silicon-based structures. The purpose of the work - the physical laws of formation thermo- acoustic response in heterogeneous structures based on silicon when the laser irradiation. Research methods - periodic and pulsed methods modulating laser, thermal and acoustic waves in inhomogeneous semiconductor structures, measurement of their parameters; numerical modeling techniques. The model - photo acoustic transformation in heterogeneous structures based on silicon under irradiation periodically modulated laser. Experimentally photo acoustic methods with gas microphone and piezoelectric method informative signal defined thermal properties of porous silicon layer on a mono crystalline silicon substrate. The regularities of the connection between the thermal parameters of the heterogeneous structures based on silicon with the parameters of the photo acoustic signal measured experimentally. Non-linear character of the dependence of the amplitude of the laser ultrasonic response from the intensity of the radiation (l = 532 nm and 694 nm) for the single-crystal silicon samples was established. Based on modeling to determine the contribution of the temperature dependence of the coefficient of thermal expansion and the thermal conductivity of the material forming the non-linear nature of the magnitude of the laser ultrasonic response. The simulation results are in good agreement with the experimental data. It is found that the presence of layers with different porosity value when forming a laser ultrasonic reaction leads to a more efficient excitation of the acoustic signal in complex systems, such as "porous silicon on a mono crystalline silicon substrate." ACOUSTIC WAVES, THERMAL WAVES, PHOTOACOUSTICS, PHOTO ACOUSTIC CONVERSION, PHOTOTHERMAL CONVERSION, SILICON, POROUS SILICON, THE SEMICONDUCTOR STRUCTURE. Product Description popup.authors Ісаєв Микола Вікторович Андрусенко Дмитро Анатолійович Войтенко Катерина Володимирівна Кузьмич Андрій Григорович Максименко Олександр Миколайович popup.nrat_date 2020-04-02 Close