The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 08, 2006
Filed:
Nov. 05, 2001
Nathan F. Gardner, San Jose, CA (US);
Fred A. Kish, San Jose, CA (US);
Herman C. Chui, Sunnyvale, CA (US);
Stephen A. Stockman, Morgan Hill, CA (US);
Michael R. Krames, Mountain View, CA (US);
Gloria E. Hofler, Sunnyvale, CA (US);
Christopher Kocot, Palo Alto, CA (US);
Nicolas J. Moll, La Honda, CA (US);
Tun-sein Tan, Los Altos Hills, CA (US);
Nathan F. Gardner, San Jose, CA (US);
Fred A. Kish, San Jose, CA (US);
Herman C. Chui, Sunnyvale, CA (US);
Stephen A. Stockman, Morgan Hill, CA (US);
Michael R. Krames, Mountain View, CA (US);
Gloria E. Hofler, Sunnyvale, CA (US);
Christopher Kocot, Palo Alto, CA (US);
Nicolas J. Moll, La Honda, CA (US);
Tun-Sein Tan, Los Altos Hills, CA (US);
Philips Lumileds Lighting Company, LLC, San Jose, CA (US);
Abstract
The extraction efficiency of a light emitting device can be improved by making the absorbing device layers as thin as possible. The internal quantum efficiency decreases as the device layers become thinner. An optimal active layer thickness balances both effects. An AlGaInP LED includes a substrate and device layers including an AlGaInP lower confining layer of a first conductivity type, an AlGaInP active region of a second conductivity type, and an AlGaInP upper confining layer of a second conductivity type. The absorbance of the active region is at least one fifth of the total absorbance in the light-emitting device. The device optionally includes at least one set-back layers of AlGaInP interposing one of confining layer and active region. The p-type upper confining layer may be doped with oxygen improve the reliability.