Rare Earth Phosphors
Original Publication Date: 1984-May-01
Included in the Prior Art Database: 2005-Feb-03
An amorphous film or powder of an efficient UV or electron-beam-excited phosphor is made up of SiO2, Al2O3, at least one of CaO and MgO, and a rare earth oxide such as Eu2O3 . The regions of good brightness exist in two systems. (Image Omitted) Five solutions of the individual ingredients are made up and blended to make a blend that can be spun-on a flat substrate, such as silicon or sapphire. The film is dried and becomes a glassy oxide upon heating to N460ŒC. Further heating to 800-1000ŒC will not produce much change. (Image Omitted) Spinning at N1000 RPM produces a film that is N4000 A thick after 460ŒC. More layers may be added. Powder of these compositions can be made by reacting fine oxides and/or carbonates to 1000-1200ŒC. The DOW Z6040 is especially stable when blended and forms the thickest films.