SEMICONDUCTOR LASER DEVICE

摘要

On a buffer layer (32) composed of n-GaAs are formed, as shown in the Fig., a clad layer (31) composed of n-AlGaAs; a waveguide layer (30); a carrier block layer (29); a side barrier layer (28) composed of non-doped AlGaAs; an active layer (27) including two quantum well layers of non-doped GaAs and a barrier layer of AlGaAs; a side barrier layer (26) composed of non-doped AlGaAs; a carrier block layer (25) composed of p-AlGaAs; a waveguide layer (23), a clad layer (22); and a cap layer (21) composed of p-GaAs in the order mentioned. In the waveguide layer (23) are formed current constriction layers (24), having a low refractive index resulting from its aluminum content more than that in the waveguide layer (23), which sandwich a striped active region (34). Thus, a difference in the refractive index appears between the active region (34) and a buried region (33) in which the current constriction layers (24) exist, thereby to form a refractive index waveguide structure. There is thus obtained a semiconductor laser device of the refractive index waveguide type that features a high output and can be easily fabricated.