Diffusional relaxation in ZnS after thermal doping at 800°C

Abstract

Photoluminescence spectra of powdered ZnS thermally doped with MnS are studied. Correlations are demonstrated between variations in the luminescence characteristics of ZnS:Mn, on one hand, and some features of radiation center formation and the diffusion of Mn in ZnS after processing, on the other. It is found that after manganese doping at a temperature (T = 800 o C) lower than the phase transition temperature of ZnS, relaxation processes owing to diffusion of Mn in ZnS take place in the material over times as long as 6⋅10 3 h. It is shown that 6⋅10 3 h after doping the α-MnS phase is essentially completely dissolved in the volume of the ZnS. Diffusion of Mn in powdered ZnS is found to occur via several channels, rapid diffusion along interior boundaries and slow diffusion via interstitial space, which indicates the existence of different activation energies for diffusion of Mn depending on its localization within the ZnS lattice.

New insight on the interaction of self-activated and Mn-related emission centers in ZnS

“…This can result in both the increase of concentration of sulfur vacancies and the appearance of oxygen-related centers because of oxygen diffusion through these vacancies. It should be noted that a high enough intensity of SA emission in the doped crystal indicates the low doping level because the Mn doping of ZnS suppresses SA emission [4,41].…”