Surface chemical changes of CaTiO3:Pr3+ upon electron beam irradiation

Surface chemical changes of CaTiO3:Pr3+ phosphor material and their effect on the red emission intensity of the 1D2→3H4 transition of Pr3+, upon electron beam irradiation are presented. Red emission at 613 nm was obtained upon probing the surface with a 2 keV electron beam. The surface chemical changes and Pr3+ red emission were monitored using an Auger Electron Spectroscopy (AES) and Cathodoluminescence (CL) spectrometer, respectively. The CL intensity decreased with a decrease in O on the surface at 1×10−8 Torr base pressure and decreased with an increase in O on the surface at 1×10−6 Torr O2. The X-ray Photoelectron Spectroscopy (XPS) revealed that CL degradation at 1×10−6 Torr O2 is due to the formation of CaO and CaOx as well as TiO2/Ti2O3 non-luminescent species on the surface.