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:
Sep. 11, 2001
Filed:
Oct. 06, 1997
Applicant:
Inventor:
Seiichi Miyazawa, Zama, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L 3/300 ; H01S 3/19 ;
U.S. Cl.
CPC ...
H01L 3/300 ; H01S 3/19 ;
Abstract
An optical semiconductor device includes a substrate and an active region formed on the substrate. The active region includes a plurality of quantum well layers containing at least one tensile-strained well layer, and the plurality of quantum well layers include a plurality of quantum well layers whose band gaps are different from each other. Such an active region makes it possible to expand a wavelength range over which TE-mode and TM-mode gains balance with each other or are approximately equal to each other.