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Information × Registration Number 0224U001316, 0121U110388 , R & D reports Title Physical properties of multi-valley semiconductors and LED structures in radiation, thermal, and deformation fields popup.stage_title Head Haidar Halyna P., Доктор фізико-математичних наук Registration Date 21-01-2024 Organization Institute of Nuclear Research of the National Academy of Sciences of Ukraine popup.description2  Anisotropy of the field dependences of galvanomagnetic effects in uncompensated p-Ge crystals of various crystallographic orientations was revealed, both under the influence of deformation and without it. It was established that isoenergetic surfaces arising as a result of directed deformation cannot be considered the perfect ellipsoids of rotation in the pressure range up to 1 GPa. In compensated p-Ge crystals, it was shown that: 1) with a monotonic increase in pressure, the field dependences of the transverse magnetotensoresistance show non-monotonic changes; 2) the dependences of changes in tensomagnetoresistance with a monotonic increase in pressure are characterized by the presence of a minimum, which, with increasing magnetic field strength, shifts to the region of lower pressures. It was established that after irradiation of high-power InGaN/GaN LEDs with fast neutrons, the magnitude and sign of the change in tunnel currents significantly depend on the substrate on which they are formed. It was found that in a structure on a silicon-carbon substrate, the current of direct current-voltage characteristic in the voltage range from zero to 1.7 V increases by 10–100 times, and in a structure on a silicon substrate with a gold-tin contact, the tunneling current does not change. It was established that LEDs on a silicon-carbon substrate have better electrical and luminescent characteristics, but irradiation significantly changes their characteristics. It was established that irradiation of green LEDs with quantum wells, which was made based on a solid solution of indium gallium nitride, with electrons with an energy of 2 MeV, leads to a decrease in their luminescence intensity due to the introduction of deep non-radiative levels mainly into quantum wells. It was revealed that an increase in differential resistance and an increase in the barrier potential occur due to a decrease in the concentration of carriers in quantum wells. Product Description popup.authors Yermolchyk Volodymyr Oleksandrovych Varnina Valentyna Ivanivna Lytovchenko Petro Grygorovych Makykha Oleksandr Mykolaiovych Malyi Evgen Viktorovych Pinkovska Myroslava Bohdanivna Petrenko Ihor Vitaliovych Starchyk Margaryta Ivanivna Tartachnyk Volodymyr Petrovych popup.nrat_date 2024-01-21 Close