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:
Jun. 10, 2008
Filed:
Jun. 21, 2005
Chen Ou, Hsin-Chu, TW;
Ting-yang Lin, Hsin-Chu, TW;
Shih-kuo Lai, Hsin-Chu, TW;
Epistar Corporation, Hsin-Chu, TW;
Abstract
A light-emitting device includes a substrate, a first nitride semiconductor stack formed on the substrate, a nitride light-emitting layer formed on the first nitride semiconductor stack, a second nitride semiconductor stack formed on the nitride light-emitting layer, and a first transparent conductive oxide layer formed on the second nitride semiconductor stack. The second nitride semiconductor stack includes a plurality of hexagonal-pyramid cavities formed in an upper surface of the second nitride semiconductor stack. The plurality of hexagonal-pyramid cavities of the second nitride semiconductor stack are filled with the first transparent conductive oxide layer, and a low-resistance ohmic contact is generated at the inner surfaces of the plurality of hexagonal-pyramid cavities so as to decrease the operation voltage and improve light-emitting efficiency of the light-emitting device.