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Information × Registration Number 0211U005900, 0110U004834 , R & D reports Title Laser-induced by nanosecond pulses processes of mass-transfer and forming of inversion and vary-band layers in solid solutions based on the cadmium telluride. popup.stage_title Head Vlasenko Alexandr Ivanovich, Registration Date 14-12-2011 Organization Institute of Semiconductor Physics of National Academy of Sciences of Ukrain popup.description2 The process of generation and propagation of shock wave (SW) is in detail studied in CdTe, solid solution based on the CdTe and structure In/CdTe at nanosecond laser irradiation. Mass-transfer related with the shock wave is investigated. For the generation of a big nonlinear acoustic pulse with further formation of shock wave semiconductors were exposed by pulses with 20 ns duration in the area of band to band absorption. Depending on laser pulse intensity the depth of shock wave formation is calculated in CdTe, Сd1-xHgxTe and in a metal indium which is used as dopant in CdTe. It is established that at the powerful nanosecond laser irradiation of the structures metall/CdTe (CdMeTe) with formation of inverse layers the dominant mechanisms of the mass-transfer are ultra-fast generation of temperature and pressure, second-rate is a process of generation, propagation and attenuation of shock wave, because it appears in the volume of semiconductor, but not on the surface, or does not appear quite - at the small crystals thicknesses and at small laser pulse intensities. It is established that the change of composition x, namely local mass-transfer of mercury in the vary-band layers of Сd1-xHgxTe on the depths which exceed length of laser radiation absorption and thermal diffusion, takes place due to the considerable gradient of pressure of the shock wave. On the example of CdTe is shown, that shock wave in a solid state body at generation, propagation, and also before origin - due to the gradual increase of gradient of the pressure - results in formation of dislocations. Thus the dislocations density is increased with a depth and is maximal in the place of the shock wave formation. It is shown that it is possible locally to influence a shock wave on the defect subsystem on the different depth of CdTe crystal and solid solution. The simultaneously operating mechanisms of the formation of SW are analyzed in a semiconductor at the nanosecond laser irradiation in general case. It the fast heating, fast phase transition, ablation, evaporation with an optical breakdown in vapors. It is important at a study and prognostication of processes of mass-transfer, shock deformation and according the generation of compression pulse at the nanosecond laser irradiation of structures metall/CdTe (CdMeTe) and solid solution with formation of the inverse and vary-band layers. Product Description popup.authors Бойко М.І. Велещук В.П. Власенко З. К. Власенко О. І. Гнатюк В.А. Киселюк М.П. Левицький С. М. popup.nrat_date 2020-04-02 Close