DFB SEMICONDUCTOR LASER DEVICE

摘要

A distributed feedback (DFB) semiconductor laser device has a multiple-quantum-well (MQW) structure and a diffraction grating formed in the MQW structure. The diffraction grating includes a grating structure formed in QW layers and a barrier layer of the MQW structure and an embedded layer embedded in the grating structure. One of the QW layers and the barrier layers has an etching rate lower than the etching rate of the other layers of the MQW structure and functions as an etching stop layer during etching of the MQW structure for forming the diffraction grating.