Trapping properties of cadmium vacancies inCd1−xZnxTe

Abstract

The trapping and thermal emission of holes were studied from a deep acceptor level created during thermal annealing of a ${\mathrm{Cd}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{Zn}}_{\mathrm{x}}$Te (x=0.12) crystal grown by the high-pressure Bridgman (HPB) technique using thermoelectric-effect spectroscopy and thermally stimulated current experiments. The deep level, which is usually absent in as-grown HPB ${\mathrm{Cd}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{Zn}}_{\mathrm{x}}$Te crystals, is assigned to the 2-/- acceptor level of Cd (Zn) vacancies. The thermal ionization energy of the level is ${\mathrm{E}}_{\mathrm{th}}$ =(0.43\ifmmode\pm\else\textpm\fi{}0.01) eV, and the trapping cross section of holes was found to be \ensuremath{\sigma}=(2.0\ifmmode\pm\else\textpm\fi{}0.2)\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}16}$ ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}2}$.