Patent ID: 8472490

Claim:
A semiconductor optical element, comprising: a p-type semiconductor substrate; a mesa-stripe-shaped laminated structure including a p-type cladding layer, an active layer, and an n-type cladding layer, arranged in that order, from the p-type semiconductor substrate; and a burying layer structure located adjacent and contiguous to opposed sides of the mesa-stripe-shaped laminated structure, wherein: the burying layer structure includes, laminated, a first p-type semiconductor layer, an n-type semiconductor layer, an Fe-doped semiconductor layer, a low carrier concentration semiconductor layer, and a second p-type semiconductor layer, arranged in that order from the p-type semiconductor substrate, alongside the mesa-stripe-shaped laminated structure, toward the n-type cladding layer, each of the first p-type semiconductor layer, the n-type semiconductor layer, and the Fe-doped semiconductor layer has, proximate the sides of the mesa-stripe-shaped laminated structure, a (111)B surface, with the (111)B surfaces of the first p-type semiconductor layer, the n-type semiconductor layer, and the Fe-doped layer, lying in respective planes at the opposed sides of the mesa-stripe-shaped laminated structure, the Fe-doped semiconductor layer is not present on the (111)B surface of the first p-type semiconductor layer, the Fe-doped semiconductor layer is not present on the (111)B surface of the n-type semiconductor layer, the low carrier concentration semiconductor layer is present on the (111)B surface of the first p-type semiconductor layer, the low carrier concentration semiconductor layer is present on the (111)B surface of the n-type semiconductor layer, and the low carrier concentration semiconductor layer is present on the (111)B surface of the Fe-doped semiconductor layer.