Distributed feedback semiconductor laser device and a method of producing the same

摘要

A distributed feedback semiconductor laser device comprising a current blocking structure having a stripe groove, and a diffraction grating formed in the bottom of the stripe groove. The current blocking structure is formed over an active layer for laser oscillation, and it includes an etch stop layer against a groove etching in a lower potion of the current blocking structure. The refractive index distribution in transverse directions inside the stripe groove is controlled by the thickness of the optical guiding layer, enabling oscillation of the fundamental transverse mode.