Luminescence and Trapping in Phosphors Containing Gallium

Publisher Website
Google Scholar
Abstract
A study was made of the effects of gallium impurity on the luminescence emission and trapping in phosphors with oxygen‐dominated host crystals and in phosphors with zinc sulfide host crystal. Gallium acts (1) as an intensifier for host‐crystal emissions in zinc silicate, magnesium silicate, and zinc sulfide phosphors; (2) as an originative activator in zinc germanate phosphor; (3) as a poison for emissions resulting from manganese activator in silicate and germanate phosphors, and for emissions caused by copper and manganese in zinc sulfide phosphors for cathode‐ray excitation; (4) as a sensitizer for emissions resulting from copper and manganese in zinc sulfide phosphors for ultraviolet excitation; (5) as a trapping agent in zinc silicate, magnesium silicate, zinc germanate, and zinc sulfide; (6) as a trapping poison in beryllium silicate phosphors. Evidence is found for a correlation between types of emission centers and trapping centers in silicate and germanate phosphors. Results on intensification indicate that intensifier activators are effective in increasing the intensity of host‐crystal emissions by introducing crystal defects of the same type as those formed by random thermal processes in the preparation of the phosphor.