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:
Dec. 02, 2008
Filed:
Jan. 04, 2006
Takahiko Kawahara, Yokohama, JP;
Nobuyuki Ikoma, Yokohama, JP;
Takahiko Kawahara, Yokohama, JP;
Nobuyuki Ikoma, Yokohama, JP;
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
The present invention is to provide a semiconductor laser with a feedback grating comprised of InP and AlGaInAs without InAsP put therebetween, and to provide a method for manufacturing the DFB-LD having such grating. The LD includes an n-type InP substrate, an AlInAsP intermediate layer, an AlGaInAs lower SCH layer, an active layer, and a p-type layer for upper cladding in this order from the InP substrate. The InP substrate, the AlInAsP intermediate layer, and the AlGaInAs lower SCH layer constitute the feedback grating. The AlInAsP intermediate layer lowers a series resistance along these semiconductor stacks.