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:
May. 24, 2011
Filed:
Jul. 25, 2008
Yoshiki Saito, Aichi-ken, JP;
Yasuhisa Ushida, Aichi-ken, JP;
Yoshiki Saito, Aichi-ken, JP;
Yasuhisa Ushida, Aichi-ken, JP;
Toyoda Gosei Co., Ltd., Nishikasugai-gun, Aichi-ken, JP;
Abstract
A characteristic feature of the invention is to form, in a Group III nitride-based compound semiconductor device, a negative electrode on a surface other than a Ga-polar C-plane. In a Group III nitride-based compound semiconductor light-emitting device, there are formed, on an R-plane sapphire substrate, an n-contact layer, a layer for improving static breakdown voltage, an n-cladding layer made of a multi-layer structure having ten stacked sets of an undoped InGaN layer, an undoped GaN layer, and a silicon (Si)-doped GaN layer, a multi-quantum well (MQW) light-emitting layer made of a combination of InGaN well layers and GaN barrier layers stacked alternatingly, a p-cladding layer made of a multi-layer structure including a p-type AlGaN layer and a p-InGaN layer, and a p-contact layer (thickness: about 80 nm) made of a stacked structure including two p-GaN layers having different magnesium concentrations. Through etching, the n-contact layer having a thickness direction along the c-axis is provided with stripe-patterned microditches each having side walls, which assume a C-plane, whereby ohmic contact is established between a negative electrode and each C-plane side wall.