Patent ID: 6222867
Filing Date: 2001-04-24
Classification: B82Y,H01S

Abstract:
An optical semiconductor device comprising:an n-InP substrate having a laser portion and a modulator portion, the laser portion being formed with a corrugation;an InGaAsP layer formed on a top surface of the n-InP substrate, wherein the lnGaAsP layer is formed in a region including the corrugation;a waveguide mesa formed on both the laser portion and the modulator portion. the waveguide mesa being thicker in the laser portion than in the waveguide portion; andan InP current blocking laver formed above and around the waveguide mesa,wherein the waveguide mesa comprises:an eight-period MQW active layer;an InGaAsP light confning layer; anda p-InP cladding layer,wherein the InP current blocldng layer comprises:a first p-InP layer having a first carrier concentration;an n-InP layer having a second carrier concentration greater than the first carrier concentration, the n-InP layer being formed directly on the first p-InP layer;a second p-InP layer having the first carrier concentration, the second p-InP layer being formed directly on the n-InP layer; anda third pInP layer having the second carrier concentration, the third p-InP layer being formed directly on the second p-InP layer.