Patent ID: 8306072
Filing Date: 2012-11-06
Classification: B82Y,H01S

Abstract:
1. A semiconductor laser device comprising: a lower cladding layer; an active layer disposed on the lower cladding layer; an upper cladding layer disposed on the active layer; a diffraction-grating layer disposed on the upper cladding layer, the diffraction-grating layer including periodic projections and recesses; a buried layer disposed on the periodic projections and recesses in the diffraction-grating layer; a mesa structure including the active layer, the mesa structure having a pair of lateral surfaces facing each other; a first semiconductor buried layer of a first conductivity type; a second semiconductor buried layer of a second conductivity type; and an electrode disposed on the first semiconductor buried layer and another electrode disposed on the second semiconductor buried layer; wherein the first semiconductor buried layer is disposed on one of the lateral surfaces of the mesa structure; and the second semiconductor buried layer is disposed on another one of the lateral surfaces of the mesa structure; and the mesa structure is buried with the first and second semiconductor buried layers, wherein the diffraction-grating layer and the buried layer constitute a diffraction grating, the lower cladding layer, the active layer, and the upper cladding layer constitute a first optical waveguide, the active layer constituting a first core region in the first optical waveguide, the upper cladding layer, the diffraction-grating layer, and the buried layer constitute a second optical waveguide, the diffraction-grating layer constituting a second core region in the second optical waveguide, the first optical waveguide and the second optical waveguide are optically coupled through the upper cladding layer and the buried layer is composed of a dielectric material.