Electrical and optical characteristics of deep levels in vanadium-doped Cd0.96Zn0.04Te materials by photoinduced current, capacitance, and photocapacitance transient spectroscopies

A complete quantitative analysis of electrical and optical properties is carried out on the vanadium transition metal in semi-insulating and n type conductor Cd0.96Zn0.04Te crystals using deep level transient spectroscopy, deep level optical spectroscopy, and photoinduced current transient spectroscopy. Four deep levels are mainly detected, with activation energies at Ec−0.95 eV, Ec−0.78 eV, Ev+0.68 eV, and Ev+0.2 eV. Their electrical and optical characteristics (thermal and optical cross sections, concentrations, and apparent activation energies) are determined. The 0.68 eV hole level and the 0.95 eV electron trap are related to the vanadium doping. These two levels are proposed to be originated from the same defect that interacts with the valence and conduction band, respectively. We have demonstrated that the 0.95 and 0.78 eV electron traps present capture barrier energies with values of 0.2 and 0.15 eV, respectively. The observed resonance bands on the optical cross sections σno and σpo of the 0.95 eV...