Experimental conditions for a growth of near stoichiometric high resistive CdTe single crystals with a minimized concentration of point defects have to be defined. The position of the stoichiometric line in the pressure-temperature (P-T) phase diagram was evaluated from high-temperature in situ galvanomagntic measurements. Calculations based on a model of two major native defects (Cd vacancy and Cd interstitial) show, that a very small variation of Cd pressure P_{Cd} results in a strong generation of uncompensated native defects. Modelling of room temperature carrier density in dependence of the deep defect density NDD, PCd, and annealing temperature T shows, that the range of optimal PCd, at which the high resistivity can be reached, broadens with increasing NDD or decreasing T. It is shown, that at low T<450 degree(s)C the deep defect density <1015cm-3 is sufficient to grow the high resistive CdTe. CdTe doped with Vanadium is used as a model example.
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