Self-compensation processes in CdTe⟨In⟩ crystals

High temperature equilibrium in situ in CdTe(In) single crystals in a wide range of temperature (700-1200 K) and dopant content (6 x 10(16)similar to 10(20) at/cm(3)) was studied. Self-compensation processes, which occur at these conditions, were modelled using quasichemical defect reaction theory. During heating the self-compensation degree passed through a minimum under Cd saturation and increased under Te saturation. The annealing under Te saturation allowed obtaining high resistive material of both conductivity types. The lowest charge carrier density was equal to similar to 3 x 10(9) cm(-3) and the self-compensation degree reached 100%. Point defect structure modelling showed a good agreement for both high temperature equilibrium and quenched state. (C) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.