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:
Sep. 28, 2004
Jen-chau Wu, Hsinchu, TW;
Chung-cheng Tu, Taipei, TW;
Pao-i Huang, Chiayi, TW;
Epistar Corporation, Hsinchu, TW;
Abstract
A high luminance indium gallium aluminum nitride light emitting diode (LED) is disclosed, including a substrate, a first conductive type nitride layer, an active layer, a second conductive type nitride layer, a first contact layer, a second contact layer, and a conductive transparent layer. The first contact layer has a first bandgap and a first doping concentration, and is disposed on the second conductive type nitride layer. The second contact layer has a second bandgap and a second doping concentration, and is disposed on the first contact layer. The first doping concentration and the second doping concentration are respectively larger than a predetermined concentration, and the first bandgap is smaller than the second bandgap. The second contact layer is thinner than a predetermined thickness so that a tunneling effect occurs between the conductive transparent layer and the second contact layer while the LED is in operation.