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:
Jul. 01, 2014
Filed:
Oct. 08, 2009
Tetsuo Fujii, Goleta, CA (US);
Yan Gao, Durham, NC (US);
Evelyn L. HU, Goleta, CA (US);
Shuji Nakamura, Santa Barbara, CA (US);
Tetsuo Fujii, Goleta, CA (US);
Yan Gao, Durham, NC (US);
Evelyn L. Hu, Goleta, CA (US);
Shuji Nakamura, Santa Barbara, CA (US);
The Regents of the University of California, Oakland, CA (US);
Japan Science and Technology Agency, Saitama Prefecture, JP;
Abstract
A gallium nitride (GaN) based light emitting diode (LED), wherein light is extracted through a nitrogen face (N-face) of the LED and a surface of the N-face is roughened into one or more hexagonal shaped cones. The roughened surface reduces light reflections occurring repeatedly inside the LED, and thus extracts more light out of the LED. The surface of the N-face is roughened by an anisotropic etching, which may comprise a dry etching or a photo-enhanced chemical (PEC) etching.