Role of intrinsic defects and impurity atoms in the formation of local centres in cadmiumsulphide single crystals irradiated with thermal neutrons and fast electrons

The effect of irradiation with thermal neutrons at low and high dose levels on TSC and PLS of “pure” and Ag-doped CdS single crystals has been investigated. Following the small dose of irradiation (1015 n/cm2) two low temperature peaks of TSC at 51 K and 78 K increased or appeared as a result of (n, γ) reaction on 114Cd. We supposed their connection with intrinsic defects of CdS. The experiment with high energy (220 keV) electron irradiation helped us to identify these peaks with Cd1 and V5 respectively. At a high dose level of irradiation (1018 n/cm2) a new peak of TSC spectra is produced. It is related with In formed by transmutation of 115Cd. Two bands in PLS are dominant after irradiation: R-band (λmax. = 0.73 μm) and IRc o-band (λmax = 1.04 μ). Their peculiarity is the temperature quenching with activation energy (0.2 ± 0.03) eV and (0.05 ± 0.02) eV respectively. Models of this radiative transition and nature of DA pairs responsible for them are speculated.