Patent ID: 6580738
Filing Date: 2003-06-17
Classification: H01S

Abstract:
A semiconductor laser device comprising:a GaAs substrate of a first conductive type; a lower cladding layer of said first conductive type, formed on said GaAs substrate; a lower optical waveguide layer made of InGaP of an undoped type or said first conductive type, and formed on said lower cladding layer; an active layer made of InGaAsP or InGaAs, and formed on said lower optical waveguide layer except for near-edge areas of said lower optical waveguide layer which are adjacent to opposite end faces of said semiconductor laser device, where said opposite end faces are perpendicular to a direction of laser light which oscillates in said semiconductor laser device; a first upper optical waveguide layer made of InGaP of an undoped type or a second conductive type, and formed on said active layer; a second upper optical waveguide layer made of InGaP of an undoped type or said second conductive type, and formed over said first upper optical waveguide layer and said near-edge areas of said lower optical waveguide layer; an upper cladding layer of said second conductive type, formed on said second upper optical waveguide layer; and a contact layer of said second conductive type, formed on said upper cladding layer.