Low voltage cathodoluminescence properties of ZnS : Ag and Y2SiO5 : Ce phosphors with surface coatings

Cathodoluminescence and aging properties of the chemically coated blue FED phosphors, ZnS : Ag and Y2SiO5 : Ce, were investigated. The luminance efficiency of ZnS : Ag and Y2SiO5 : Ce phosphors were increased with MgO and Al-compound coatings. However, this increase was associated with the presence of a small side-peak at the long wavelength part of the emission spectrum that resulted in degradation of color coordinates. For the case of Si-compound coating, it was found that the luminance efficiency and peak emission intensity of Y2SiO5 : Ce phosphor were considerably increased without any noticeable change in color chromaticity. Also, Si-compound coating on Y2SiO5 phosphor was found to be effective for improving the aging property.