Characterization of CdTe with photoelectronic techniques

Abstract

Thermally stimulated current (TSC) and space-charge limited current (SCLC) measurements have been performed in CdTe grown by Bridgman method with various In dopings and grown from Te-rich solution with Cl doping. Hole traps have been evidenced at 0.07, 0.14, 0.25 and 0.36 eV from valence band, while electron traps are at 0.05, 0.34, 0.52 and 0.62 eV from conduction band. Measurements of activation energies of resistivity vs temperature curves indicate which of these should correspond to donors or acceptors centers. Various methods of analysis were used both for TSC and for SCLC results, in order to determine the more suitable ones. Finally TSC and SCLC are compared and discussed as methods for CdTe characterization.