Cathodoluminescence and Longevity Properties of Potential Sr_1-xM_xGa₂S₄:Eu (M = Ba or Ca) Green Phosphors for Field Emission Displays

Abstract

We report the cathodoluminescence and aging properties of a series of green phosphors of formula Sr 1-x M x Ga 2 S 4 :Eu (x = 0.0-1.0, M = Ba or Ca) that have potential applications in field emission displays (FEDs). The series of phosphors was synthesized via NaBr-aided solid-state reactions in a flowing H 2 S stream. A low level (~20%) of Ba or Ca substitution for Sr in SrGa 2 S 4 :Eu maintains the orthorhombic phase of pure SrGa 2 S 4 :Eu phosphors. Further, a low level (~20%) of Ba or Ca substitution for Sr in SrGa 2 S 4 :Eu provides various green colors and sufficient brightness for FED applications. Substitution of Ba or Ca for Sr in SrGa 2 S 4 :Eu also improved the stability of the phosphor when it was operated under electron-beam irradiation of 5 kV.