Low-voltage cathodoluminescence properties of the Y2O2S : Eu red light emitting phosphor screen in field-emission environments

Abstract

Y2O2S: Eu phosphors doped with different concentrations of Eu were fabricated by a high-temperature flux fusion method. For applications in field emission displays, phosphor powders were electrophoretically deposited on an indium-tin oxide coated glass substrate to form a phosphor screen. Cathodoluminescence properties of phosphor screens were examined at a low excitation voltage of 5 kV in a high-vacuum chamber (5 x 10(-8) Torr), and characteristics of Y2O2S: Eu phosphors, including brightness and wavelength data, are presented and discussed. The red emission brightness for the Y2O2S: Eu phosphor screens can be significantly improved by adjustment of the Eu additions, which decrease the x coordinate slightly, while having no significant influence on the color performance. Considering the effects of Eu concentrations on red light emission spectra and brightness for Y2O2S: Eu phosphor screens, it is found that brightness for Y2O2S: Eu phosphor screens could be obtained up to 120 cd/m(2) with chromaticity of x = 0.63 and y = 0.36, and the Eu dopant concentration is suggested to be in the range 6-7.5 wt %. (C) 2002 The Electrochemical Society.