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:
Feb. 05, 2019
Filed:
Oct. 02, 2017
Epistar Corporation, Hsinchu, TW;
EPISTAR CORPORATION, Hsinchu, TW;
Abstract
A light-emitting device is provided. The light-emitting device comprises The light-emitting device comprises a light-emitting stack comprising a first semiconductor layer, a second semiconductor layer and an active layer between the first semiconductor layer and the second semiconductor layer; and a third semiconductor layer on the light-emitting stack and comprising a first sub-layer, a second sub-layer and a roughened surface, wherein the first sub-layer has the same composition as that of the second sub-layer, and the second sub-layer is farther from the light-emitting stack than the first sub-layer; wherein the first sub-layer and the second sub-layer each comprises a Group III element and a Group V element, and an atomic ratio of the Group III element to the Group V element of the first sub-layer is less than an atomic ratio of the Group III element to the Group V element of the second sub-layer.