Patent ID: 6285695
Filing Date: 2001-09-04
Classification: B82Y,H01S

Abstract:
A semiconductor laser comprising: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.sub.1-y2 P.sub.y2 (0.ltoreq.y2.ltoreq.1),a quantum-well active layer of In.sub.x3 Ga.sub.1-x3 As.sub.1-y3 P.sub.y3 (0.ltoreq.x 3.ltoreq.1, 0.ltoreq.y3.ltoreq.1),a second barrier layer of GaAs.sub.1-y2 P.sub.y2 (0.ltoreq.y2.ltoreq.1),a second optical waveguide layer, anda second clad layer having the of p-type conductivity and n-type conductivity formed in this order on a GaAs substrate,wherein each of the first and second clad layers is of a composition which matches with the GaAs substrate in lattice,wherein each of the first and second optical waveguide layers is of a InGaAsP composition which matches with the GaAs substrate in lattice, p1 wherein each of the first and second barrier layers is 10 to 30 nm in thickness and is of a composition which has tensile strain to the GaAs substrate,wherein the product of the tensile strain and the thickness of each of the first and second barrier layers being 5 to 20% nm,wherein the quantum-well active layer of In.sub.1-x3 Ga.sub.1-x3 As.sub.1-y3 P.sub.y3 is 6 to 10 nm in thickness and is of composition which has compressive strain of not smaller than 1.0% relative to the GaAs substrate can realize oscillation at 950 to 1100 nm, andwherein a sum of a product of the tensile strain and the thickness of the first barrier layer and that of the second barrier layer is larger than a product of the compressive strain and the thickness of the quantum-well active layer.