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. 08, 2001
Filed:
Dec. 18, 1997
Katsuhiko Nisitani, Kanagawa-ken, JP;
Kazumi Unno, Kanagawa-ken, JP;
Masayuki Ishikawa, Kanagawa-ken, JP;
Ryo Saeki, Chiba-ken, JP;
Takafumi Nakamura, Fukuoka-ken, JP;
Masanobu Iwamoto, Fukuoka-ken, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A semiconductor light emitting device has a double heterostructure. The device is composed of an active layer and clad layers that sandwich the active layer. At least one of the clad layers has a multilayer structure having at least two element layers. The Al mole fraction of an element layer, which is proximal to the active layer, of the multilayer structure is smaller than that of the other element layer thereof distal from the active layer. This arrangement improves the crystal quality of an interface between the active layer and the clad layer of multilayer structure and effectively confines carriers in the active layer.