  The process of self-compensation in Cd0.95Zn0.05Te:Cl solid-solution crystals
has been studied by annealing single crystals under a controlled Cd vapor
pressure, with subsequent measurements of the Hall effect, photoluminescence,
carrier lifetime and mobility, and photocurrent memory in the annealed
crystals. By means of this annealing, conditions of thermal treatment that make
it possible to fabricate low-conductivity samples with a low carrier density,
10E7-10E11 cm-3, are denned. In these samples, a p -- n conduction inversion is
observed at a higher free-carrier density ((n, p) near 10E9 cm-3) and the
dependence of the electron density on the Cd vapor pressure exhibits a more
gentle slope than in the case of CdTe:Cl crystals.
  The obtained data are dis-cussed in terms of a self-compensation model in
which intrinsic point defects act as acceptors with deep levels. This level is
attributed to a Zn vacancy, which remains active at high Cd pressure.
