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:
Nov. 26, 2002
Filed:
Aug. 04, 2000
Stephen Peter Najda, Oxford, GB;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
An (Al,Ga,In)P semiconductor laser device has an optical region disposed between n-type and p-type cladding layers. An active region containing quantum well active layers and barrier layers disposed alternately with the quantum well layers is provided within the optical guiding region. Strained layers of In Ga P are used as the barrier layers. The active region is thus aluminium-free, and this reduces the oxygen impurity concentration in the active region thereby improving the performance and reliability of the laser. An aluminium-free spacer layer can be provided between one of the cladding layers and the quantum well active layer disposed closest to that cladding layer. The invention may be applied to other semiconductor devices, for example such as an LED.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile