Degradation Mechanisms for CdSe Quantum dot down converted LEDs

Abstract

Lifetime of packaged white light emitting diodes (W-LEDs) using a blue LED and red quantum dot have been observed. A new phenomenon of light intensity increase during the initial lifetime is noticed followed by the rapid light output degradation. The initial increase in light output is believed to be due to photo -modification whereas the later rapid degradation is found to be due to photo oxidation mechanism.