Semiconductor laser device.

摘要

A semiconductor laser device according to the invention comprises a semiconductor substrate, a multilayered double heterostructure having an active layer and formed on said substrate and a ridge waveguide further comprises a current blocking layer formed between the semiconductor substrate and the active layer. With such an arrangement, electric current is narrowed not only on the side of the ridge of the active layer but also on the substrate side of the active layer to improve its current confinement effect. When the two lateral trenches of the ridge are embedded with resin layers, the ridge strip width can be made narrow to improve the heat conductance capability of the device. When the active layer is realized in two discrete layers and a DCC structure having an intermediary clad layer is sandwiched therebetween, the device will show a low threshold current level, a minimum theta ¦/ theta ratio and stabilized thermal characteristics. <IMAGE>