High efficiency nitride based phosphors for white LEDs

Abstract

In this overview paper, novel rare-earth doped silicon nitride based phosphors for white LEDs applications have been demonstrated. The luminescence properties of orange-red-emitting phosphors (M 2Si 5N 8:Eu 2+) and green-to-yellow emitting phosphors (MSi 2N 2 O 2:Eu 2+, M = Ca, Sr, Ba) are discussed in detail with a focus on the relationship between the properties and structures. With high conversion efficiency in the near UV/blue region, along with high chemical/physical stability, Eu 2+ - and Ce 3+ - activated alkaline-earth silicon nitride and oxynitride materials are excellent wavelength-conversion phosphors for white LEDs.