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. 04, 2001
Filed:
Feb. 09, 1999
Hideki Asano, Kanagawa-ken, JP;
Mitsugu Wada, Kanagawa-ken, JP;
Toshiaki Fukunaga, Kanagawa-ken, JP;
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
A semiconductor laser includes a first clad layer having one of p-type conductivity and n-type conductivity, a first optical waveguide layer, a first barrier layer of GaAs,P,, a quantum-well active layer of In,Ga,As,P,, a second barrier layer of GaAs,P,, a second optical waveguide layer and a second clad layer having the of p-type conductivity and n-type conductivity formed in this order on a GaAs substrate. Each of the first and second clad layers is of a composition which matches with the GaAs substrate in lattice. Each of the first and second optical waveguide layers is of a InGaAsP composition which matches with the GaAs substrate in lattice. Each of the first and second barrier layers is 10 to 30 nm in thickness and is of a composition which has tensile strain relative to the GaAs substrate, the product of the tensile strain and the thickness of each of the first and second barrier layers being 5 to 20% nm. The quantum-well active layer is 6 to 10 nm in thickness and is of a composition which has compressive strain of not smaller than 1.0% relative to the GaAs substrate. The sum of the product of the tensile strain and the thickness of the first barrier layer and that of the second barrier layer is larger than the product of the compressive strain and the thickness of the quantum-well active layer.