Mechanisms of antimony interstitial penetration into cadmium telluride crystals

The results of electrophysical investigations of CdTe crystals, grown by Bridgman method and doped with Sb impurity in concentrations for 1017-3 x 1019 cm-3 are presented. The analysis of the temperature dependence of Hall coefficient, current carrier mobility and photoconductivity at intrinsic excitation for samples taken from different parts of ingots allows to conclude, that SbTe, SbCd centers and (SbTeSbCd) associated appear in CdTe crystal during its doping by antimony impurity. The hole conductivity in doped crystals is controlled by A3 (SbTe) acceptors, their density not exceeding 5 x 1016 cm-3, and is essentially less than the real impurity content. The ionization energy of A3 acceptors is (0.28 ± 0.01) eV. In non-equilibrium conditions these acceptors play the role of adhesion centers for holes (at high temperatures) and the slow recombination centers for electrons (at low temperatures)