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:
Oct. 02, 2007
Filed:
Jul. 02, 2004
Mitsuhiro Kushibe, Tokyo, JP;
Yasuo Ohba, Kanagawa-Ken, JP;
Rei Hashimoto, Tokyo, JP;
Keiji Takaoka, Kanagawa-Ken, JP;
Mitsuhiro Kushibe, Tokyo, JP;
Yasuo Ohba, Kanagawa-Ken, JP;
Rei Hashimoto, Tokyo, JP;
Keiji Takaoka, Kanagawa-Ken, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
A low-cost high-property optical semiconductor element for a long wavelength is provided, using a GaAs substrate. The optical semiconductor element comprises a substrate of GaAs having a first surface and a second surface opposite to each other, a buffer layer of InGaAsN(0≦j≦1, 0.002≦k≦0.05) formed on the first surface of the substrate, a first conductive type clad layer formed on the buffer layer, an active layer formed on the first conductive type clad layer and comprising a well layer of InGaAs (0≦z≦1), the well layer having a smaller bandgap than the first conductive type clad layer, the active layer having a thickness of more than its critical thickness for the substrate based upon equilibrium theories, and a second conductive type clad layer formed on the active layer and having a larger bandgap than the well layer.