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The study of the electro-physical properties of n-type semi-insulating crystals of indium-doped Cd(Mn)Te solid solution with a resistivity ~ (4÷5)×1010 Ohm×cm at T = 300 K was carried out. The structures both with an ohmic (In/Cd(Mn)Te/In) contacts and with the rectifying (Ni/Cd(Mn)Te/In) contact were fabricated. It was found that for the Ni/Cd(Mn)Te/In structure, the main mechanisms of charge transport were: the generation currents in the space-charge region, space-charge limited currents (SCLC) at high voltages, and the Ohm’s law was valid only on initial section the of the volt-ampere characteristics (I-VC). Calculation of the generation current dependence on the voltage according to the theory of Sah-Noyce-Shockley was carried out. For the In/Cd(Mn)Te/In structure it was observed the I-VC initial section, where the Ohm’s law was implemented, and the SCLCs with the participation of deep centers (traps) in semiinsulating crystal - at greater voltages. The concentration of deep centers (Nt ~ 7.4×1010 cm-3 ) responsible for the trap mechanism in SCLC In/Cd(Mn)Te/In structures was calculated. The energy position Et of the deep levels was determined (provided that the energy was calculated from the valence band edge, Et = 0.89÷0.9 eV). It was discussed and grounded the assumption that SCLC was the main mechanism limiting the operating voltages and, consequently, the use of Cd(Mn)Te-based ionizing-radiation detectors with ohmic contacts.
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