Patent ID: 7050472
Filing Date: 2006-05-23
Classification: H01S

Abstract:
1. A semiconductor laser device, comprising: a substrate; an active layer formed on the substrate; an optical guiding layer on the active layer; an etch-stop layer formed on the optical guiding layer; a cladding layer provided with a stripe structure, formed on the etch-stop layer; a current blocking layer formed on the etch-stop layer and arranged at least on the sides of said stripe structure, the current blocking layer having transparency with respect to light radiated from the active layer; and a semiconductor layer provided with a diffraction grating arranged between the active layer and the optical guiding layer; wherein the substrate, the active layer, the etch-stop layer, the cladding layer, the current blocking layer, and the semiconductor layer are composed of III–V group compounds, wherein the etch-stop layer and the optical guiding layer are provided at least under the stripe structure, and the cladding layer is not in contact with the optical guiding layer and wherein the etch-stop layer either has a content of Al smaller than a content of Al in the current blocking layer and in the optical guiding layer, or has no Al, and the etch-stop layer is present over an entirety of a lower principal surface of the current blocking layer.