Open AccessWhite Light Emitting Diode Development for General Illumination Applications
Author(s) -
J. P. Ibbetson
Publication year - 2006
Language(s) - English
Resource type - Reports
DOI - 10.2172/888746
Subject(s) - light emitting diode , optoelectronics , materials science , diode , chip , silicon carbide , junction temperature , led lamp , fabrication , thermal resistance , luminous flux , watt , gallium nitride , radiant flux , optics , thermal , power (physics) , electrical engineering , nanotechnology , engineering , light source , physics , layer (electronics) , quantum mechanics , medicine , alternative medicine , pathology , meteorology , metallurgy
This report contains a summary of technical achievements during a 3-year project aimed at developing the chip and packaging technology necessary to demonstrate efficient, high flux light-emitting diode (LED) arrays using Cree's gallium nitride/silicon carbide (GaN/SiC) LED technology as the starting point. Novel chip designs and fabrication processes are described that led to high power blue LEDs that achieved 310 mW of light output at 350 mA drive current, corresponding to quantum and wall plug efficiencies of 32.5% and 26.5%, respectively. When combined with phosphor, high power white LEDs with luminous output of 67 lumens and efficacy of 57 lumens per watt were also demonstrated. Advances in packaging technology are described that enabled compact, multi-chip white LED lamp modules with 800-1000 lumens output at efficacies of up to 55 lumens per watt. Lamp modules with junction-to-ambient thermal resistance as low as 1.7 C/watt have also been demonstrated