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Information × Registration Number 0212U007438, 0112U005072 , 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 26-12-2012 Organization Institute of Semiconductor Physics of National Academy of Sciences of Ukrain popup.description2 The phenomenon of high mobility of atoms in crystals under pulsed laser irradiation (PLI) is currently of high applied importance for the solid-phase doping of CdTe and CdZnTe by means of the irradiation of metal/CdTe (CdZnTe) structures by laser pulses. For example for X-ray and gamma sensitive detectors with high spectrometric characteristics. Such mass-transfer mechanism at PLI as thermo-, baro- and concentration diffusion, evolution of laser-induced shock wave, diffusion at melting are analyzed and calculated. It is established that the dominant masstransfer mechanism at the nanosecond laser solid-phase doping of CdTe with indium is the barodiffusion. It is appropriate to provide sharp pressure gradients, rather than achievement of high value of pressure and temperature. The concentration profile of indium, cadmium and tellurium atoms in the CdTe after the single irradiation of the In/CdTe structure from the side of the 30-nm thick indium film by an excimer laser pulse (? = 248 nm, p = 20 ns) at the energy density E = 100 mJ/cm2 is measured. It is revealed, that maximum of indium profile at 6 nm corresponds to a minimum of cadmium profile that specifies on diffusion of In interstitial atoms on the Cd vacancies. Due to the different models middle drift speed of In atoms in CdTe is calculated at the nanosecond laser irradiation of structure In/CdTe in the case of solid-phase diffusion - 3...24 cm/s. Influence of factors of compression and tension of crystalline grate parts at the redistribution of doping atoms (In, Cl) and point defects due to the difference of dilatation volumes. Spectrums of low temperature (T = 20 K) photoluminescence of CdTe crystals after nanosecond laser irradiation by KrF-excimer laser and after laser-induced diffusion of In atoms from film measured and analyzed. At laser irradiation of the structure film In/ р - CdTe inverse layer (n- type) is formed, because at photoluminescence spectrums a peak А0Х (VCd - ClTe complex) disappears and a peak at 1,593 eV (D0Х)Іn appears (shallow donor In). Growth of photoluminescence intensity in the area of free excitons (short-wave area) is registered. 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