Semiconductor laser device with a sulfur-containing film provided between the facet and the protective film

摘要

A semiconductor laser device is disclosed which emits laser light from a facet. The semiconductor laser device comprises a multi-layered structure formed on a semiconductor substrate, the multi-layered structure having an AlGaAs active layer for laser oscillation, and a protective film formed on the facet, wherein a film containing sulfur is provided between the facet and the protective film.