Reliability of Nanoparticle-coated Phosphors for white LED Application

Abstract

For the application to a light emitting diode, phosphors require thermal resistance and proper optical spectra with high quantum efficiency. Specially, reliability issues are getting critical due to the harsh operating environment as the solid state lighting application is getting dominant. Here, oxynitride material system, which is not introduced into commercial market yet, is investigated. In Eu-doped MO-Si3N4 system, thermal, moisture, and photonic resistance are examined. It is found that the surface state and cystallinity are important for guaranteeing the device reliability, even though the powder chemical and optical properties are good enough, comparing to well known commercialized phosphor such as Y 3Al 5O 12:Ce and Sr 2SiO 4:Eu. ©The Electrochemical Society.