Optimization of yttrium aluminum garnet:Ce3+ phosphors for white light-emitting diodes by combinatorial chemistry method

Filament light bulbs and halogen lamps are widely used to light houses and offices but are energy inefficient. We synthesized optimal phosphors for 460 nm blue light-emitting diodes (LEDs) and fabricated white LEDs to develop energy-efficient, reliable, and long-lived solid-state lighting LED devices. GaN-based blue LEDs are the excitation source for yttrium aluminum garnet:Ce3+ (YAG:Ce3+) phosphors, and the YAG:Ce3+ phosphors convert the blue light into red and green lights. We take combinatorial chemistry method as a tool to rapidly synthesize and screen potential garnet phosphors for use as blue to yellow down-conversion phosphors in white LEDs. Using combinatorial chemistry, we find the optimal YAG: Ce3+ phosphors, (Y0.95Ce0.05)(3)Al5O12 for white LEDs. We also fabricate highly energy-efficient white light emitting diodes by combining (YAG):Ce3+ phosphors and blue LEDs. (C) 2002 The Electrochemical Society.