Tellurium Doping and Implantation of Zinc Sulphide

A detailed study of the effect of tellurium concentration on the cathodoluminescence spectra of chemically-doped zinc sulphide polycrystalline samples shows that emission from single tellurium isoelectronic centres is saturated before the emission from paired tellurium isoelectronic centres. At added tellurium concentrations of < 10−3 atomic parts only the single tellurium emission is present whereas at or above 5 × 10−2 atomic parts of tellurium only the paired tellurium emission is observed. At 10−2 atomic parts tellurium both tellurium emissions arc observed. No increase in tellurium emission intensity is observed when the tellurium concentration is increased above 5 × 10−2. The tellurium concentrations capable of producing both tellurium emission bands in polycrystalline samples are shown to produce the same behaviour in single crystals also. In addition, conditions for producing the paired tellurium emission by ion implantation are reported, along with thermal quenching measurements and time-resolved spectroscopy measurements and introduction of donors in ZnS: Te by implantation of Al.