Semiconductor laser device, a semiconductor laser array, and a method for aligning optical fibers with the device or array

摘要

A semiconductor laser device which can be aligned with an optical fiber easily, through visual observation. The laser device includes at least two active layers which are arranged at the same level relative to a surface of a semiconductor substrate, and parallel to each other with a predetermined space between. One of the active layers has its top face buried under a first semiconductor layer, which has a refractive index lower than the refractive index of that one of the active layers, to form a light emitting portion. Another one of the active layers has its top face buried under an insulating layer, which is a second semiconductor layer different in kind from the first semiconductor layer and the first semiconductor layer in this order, to form a convex non-light-emitting portion.