Characterization of thin‐film blue SrGa2S4 phosphors for low‐to‐medium‐energy cathodoluminescent displays

Abstract

Abstract— The spectral response, luminance, and outgassing characteristics of new, thin‐film Ce‐activated SrGa2S4 phosphors for application in field‐emission flat‐panel displays are presented. The tested phosphor materials are prepared using molecular beam epitaxy. The sample screens are tested with e‐beam excitation at currents up to 50 μA within the 200–2000 V (i.e., “low‐voltage”) and 3–8 kV (i.e., “medium‐voltage”) ranges. The spectral coordinates are compared to those of commercial low‐voltage phosphors. Phosphor outgassing, as a function of time, is measured with a residual gas analyzer at a fixed 50‐μA beam current in the low‐voltage range. We find that levels of outgassing stabilize to low values within the first hour of excitation. The desorption rates measured from thin films are compared to previously studied desorption parameters for powder phosphor layers.