Trapping Action in Electroluminescent Zinc Sulfide Phosphors*

The action of electron traps in electroluminescent ZnS phosphors is discussed on the basis of experimental results obtained from (a) the temperature and frequency dependence of the time-averaged electroluminescent brightness, (b) the temperature and frequency sensitivity of brightness waves, and (c) the initial rise of electroluminescent brightness. It is shown that much more importance must be ascribed to the existence of electron traps in electroluminescent phosphors than in ordinary photoluminescent phosphors.