Method for making long-life electroluminescent phosphor
AssigneeOsram Sylvania Inc.
InventorsChen-Wen Fan, Richard G. W. Gingerich, Dale E. Benjamin
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Abstract
A method of coating phosphor particles comprises introducing an inert gas into a reaction vessel and charging phosphor particles into the reaction vessel. The reaction vessel is then heated to a reaction temperature and a coating precursor is introduced while the temperature is maintained for a time sufficient to saturate the phosphor particles with the precursor. Thereafter, continuous precursor is introduced into the reaction vessel, along with an oxygen/ozone mixture. The inert gas flow, oxygen/ozone mixture flow and further precursor are supplied for a time sufficient to coat the phosphor particles.
Claims8
In a method of coating electroluminescent phosphor particles with a coating of aluminum oxide, the steps comprising:
- introducing an inert gas into a reaction vessel;
- charging phosphor particles into said reaction vessel;
- heating said reaction vessel to a reaction temperature of about 180° C.;
- introducing a coating precursor which includes at least aluminum into said reaction vessel for a time sufficient to saturate said phosphor particles with said precursor;
- continuing precursor flow into said reaction vessel;
- introducing an oxygen/ozone mixture into said reaction vessel to react with said precursor;
- and maintaining said inert gas flow, oxygen/ozone mixture flow and further precursor supply for a time sufficient to coat said electroluminescent phosphor particles with said aluminum oxide.
Dependencies are inferred from the claim text.