Nitridosilicates: a new family of phosphors for color conversion of LEDs

摘要

Phosphor-converted Light Emitting Diodes (pc-LEDs) to generate white light from blue or UV emitting diodes can be made using Eu2+ doped nitridosilicates -M2Si5N8- and/or oxo nitridosilicates -MSi2O2N2 with M=alkaline earth. Luminescence properties of some out of this new class of color converters have been investigated. As expected from strong absorption the decay times of the internally excited Eu2+ is short (around 1 microsec) and depends on the cation sharing the unit cell. Time resolved spectroscopy illustrates the behavior even more clearly. Laboratory pcLEDs using 2 of the nitride phosphors show excellent drive and temperature stability of all color properties as expected.