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. 28, 2004
Filed:
Jan. 28, 2000
Applicant:
Inventors:
Assignee:
Sharp Kabushiki Kaisha, Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01S 5/00 ;
U.S. Cl.
CPC ...
H01S 5/00 ;
Abstract
In a semiconductor laser device having a quantum well active layer, an undoped thin spacer layer is formed between an undoped optical guide layer and a p-type cladding layer. The thickness of the spacer layer is preferably 5 nm or more but less than 10 nm. The spacer layer absorbs impurities diffusing thereinto from the p-type cladding layer. Thus, the dopant is prevented from being diffused into the undoped optical guide layer.