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Information × Registration Number 0217U007312, 0115U003242 , R & D reports Title Development of scientific background of radiation detectors and solar cells based on CdTe, doped by 3d-metals (Mn, Zn) isovalence impurities popup.stage_title Head Fochuk Petro, Registration Date 28-12-2017 Organization Yuri Fedkovych Chernivtsi National University popup.description2 The researches by the method of differential-thermal analysis of the melting and crystallization processes of Cd (Zn, Mn) Te solid solutions (CdTe-MnTe, CdTe-ZnTe systems) were led. On all thermograms, endo- and exothermic effects were observed that corresponded to the melting and crystallization points that are characteristic of the congruent phase transformations. On the basis of the conducted researches, the technology of Cd (Zn, Mn) Te crystals synthesis and growth has been optimized for the development of radiation detectors. The furnace designs, temperature changes programs during the technological operations are optimized. Several methods of growing crystals have been tested: the Bridgman method and the modified traveling heater method. The simulation of the inclusion distribution of extraneous phases in the volume of crystals with the use of the developed software was carried out. For the first time, CdTe and Cd1-xMnxTe crystals were cleaned from the phase inclusions by the dry zone method. It is established that after such purification, the density and the inclusions of the Te phase in the crystal decreases several times, and the concentration of ionized impurities more than 2 times. For the first time the rotation of the container was applied at an angle to the horizon, which allowed to align the crystallization front and increase the homogeneity of the material. A complex study of the ensemble of point and volume defects in Cd(Zn,Mn)Te crystals, doped with In (Al), with optimal content of Zn or Mn was carried out. The electric characteristics of the Cd(Zn,Mn)Te crystals, doped with indium, and structures on the basis of the In/Cd(Zn,Mn)Te/In type with ohmic contacts and Cr/Cd(Zn,Mn)Te/In with barrier contacts (Schottky diodes) that were used to create X- and ?-radiation detectors. The temperature dependences of resistivity, Fermi level energy in materials with a high specific resistance were analyzed and explained. The ionization energy and the degree of compensation of the impurity, responsible for the electrical conductivity of the material, were found. Due to the coherent study of the temperature dependence of the currents of the ohmic section of the volt-ampere characteristic and the currents, limited by the spatial charge, a connection between the energy positions and the degree of compensation of the deep level responsible for the dark conductivity of the crystals and the detecting properties of the structures made on these crystals was established. Product Description popup.authors Іваніцька Валентина Григорівна Дремлюженко Сергій Григорович Копач Олег Вадимович Никонюк Євген Сергійович Панчук Олег Ельпідефорович Склярчук Валерій Михайлович Солодін Сергій Володимирович Федорчук Анатолій Олександрович Фочук Петро Михайлович Щербак Лариса Павлівна popup.nrat_date 2020-04-02 Close