Passivation of bulk trapping levels in cadmium telluride by proton implantation

Abstract

A passivation of deep levels in the bulk has been observed by thermally stimulated currents and photoinduced current transient spectroscopy for well-defined conditions of hydrogen implantation into high-resistivity, chlorine-compensated traveling heater method grown CdTe crystals. The influence of ion-induced damage during implantation has been evaluated and the passivation effect on deep levels in the bulk, especially in the range 0.3–0.4 eV, has been clearly identified. This passivation introduces a strong increase of the mobility carrier lifetime product, as shown by photoconductivity measurements, as well as an increase of resistivity. Finally, the stability of this compensation by hydrogen has been investigated.