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:
Apr. 12, 2022
Filed:
Sep. 28, 2018
Dowa Electronics Materials Co., Ltd., Tokyo, JP;
Yasuhiro Watanabe, Akita, JP;
DOWA Electronics Materials Co., Ltd., Tokyo, JP;
Abstract
Disclosed is a deep ultraviolet light-emitting device which includes on a substratein order: an n-type semiconductor layer, a light-emitting layer, a p-type electron block layer, and a p-type contact layer, wherein the p-type contact layercomprises a superlattice structure having an alternating stack of: a first layermade of AlGaN having an Al composition ratio x higher than an Al composition ratio wof a layer configured to emit deep ultraviolet light in the light-emitting layer; and a second layermade of AlGaN having an Al composition ratio y lower than the Al composition ratio x, and the Al composition ratio w, the Al composition ratio x, the Al composition ratio y, and a thickness average Al composition ratio z of the p-type contact layer satisfy the formula [1] 0.030<z−w<0.20 and the formula [2] 0.050≤x−y≤0.47.