| 摘要 |
PURPOSE:To obtain a semiconductor laser which can control the wavelength continuously, by constructing an emitting end face on the side of a control region such that it has a high optical reflectivity excessing a particular value. CONSTITUTION:A diffraction grating 1 is formed only in a portion corresponding to a laser region 2 on an N type InP substrate 11. An N type InGaAsP optical waveguide layer 12, an InGaAsP active layer 13 and a P type InP clad layer 14 are successively grown so as to cover the whole surface. The portions of the clad layer 14 and the active layer 13 corresponding to a control region 3 are then removed by etching. This wafer is provided with two parallel grooves 15 deeper than the active layer 13, and with a mesa stripes 16 between them. A P type InP block layer 17 and N type InP block layer 18 are epitaxially grown over there except for the upper face of the mesa stripe 16, and then P type InP burried layer 19 and P<+> type InGaAsP cap layer 20 are epitaxially grown so as to cover the whole surface. Further, an SiO2 film 25 and an Au film 26 are formed on the end face on the side of the control region 3 so that the optical reflectivity is as high as 50% or more. |
