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:
May. 11, 1999
Filed:
Mar. 09, 1998
Motoharu Miyashita, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A stress compensation type semiconductor laser emitting laser light of 0.98 .mu.m.about.1.02 .mu.m wavelength includes a semiconductor substrate, a cladding layer disposed on the semiconductor substrate, and a multiple quantum well structure active layer disposed on the cladding layer and comprising a plurality of well layers and barrier layers. In the laser, when the number, strain, and thickness of the well layers are n, f.sub.w, and t.sub.w, respectively, and the number, strain, and thickness of the barrier layers are m, f.sub.b, and t.sub.b, respectively, the average strain f.sub.av of the well layers and the barrier layers, and the total thickness t.sub.total of the well layers and the barrier layers is given by ##EQU1## where .upsilon. is the Poisson ratio, b.sub.o is the magnitude of a Burgers vector of a perfect dislocation, b.sub.p is the magnitude of a Burgers vector of partial dislocation, and r.sub.c is the half loop radius of a dislocation. Therefore, an active layer having required stress compensation performance is realized with high reliability and high reproducibility.