Mark K Pugh

US Patent:

7626210, Dec 1, 2009

Filed:

Jun 9, 2006

Appl. No.:

11/423419

Inventors:

Oleg Borisovich Shchekin - San Francisco CA, US
Mark Pugh - Los Gatos CA, US
Gerard Harbers - Sunnyvale CA, US
Michael R. Krames - Los Altos CA, US
John E. Epler - Milpitas CA, US

Assignee:

Philips Lumileds Lighting Company, LLC - San Jose CA

International Classification:

H01L 29/20

US Classification:

257 98, 257E31127, 385 4, 362610, 362612

Abstract:

Low profile, side-emitting LEDs are described, where all light is efficiently emitted within a relatively narrow angle generally parallel to the surface of the light-generating active layer. The LEDs enable the creation of very thin backlights for backlighting an LCD. In one embodiment, the LED is a flip chip with the n and p electrodes on the same side of the LED, and the LED is mounted electrode-side down on a submount. A reflector is provided on the top surface of the LED so that light impinging on the reflector is reflected back toward the active layer and eventually exits through a side surface of the LED. A waveguide layer and/or one or more phosphors layers are deposed between the semiconductor layers and the reflector for increasing the side emission area for increased efficiency. Side-emitting LEDs with a thickness of between 0. 2-0. 4 mm can be created.