Diffusion of charged defects in Tellurium-rich CdTe

Diffusion of charged point defects is studied theoretically in shallow-donor-doped tellurium-rich CdTe, which is typically used for a preparation of radiation detectors. Diffusion model involves complete charge defect statistics including formation of associates and internal electric field induced by the charged defect gradient. We show how extrinsic doping influences the rate of chemical diffusion, which can be both accelerated and retarded. In case of strongly compensated material at low temperatures the diffusion of compensating Cd vacancies is significantly enhanced in comparison with the undoped case and the defect relaxation is enhanced this way. The possibility to utilize this effect in the detector adjustment is discussed.