| 摘要 |
PURPOSE:To make it possible to form a noninjected region at a crystal forming stage and to improve reproducibility of characteristics and a manufacturing yield, in a distributed feedback type semiconductor laser, wherein two etching grooves, which are separated by a mesa stripe including an active layer that is recombined by light emission, have a relatively broad part and a narrow part, and the narrow part is made to be an noninjected region. CONSTITUTION:On an N type InP substrate 301, in which a diffraction grating is formed, an N type In0.85Ga0.15As0.33P0.67 optical guide layer 302 corresponding to a light emitting wavelength composition of 1.1mum and the like are sequentially laminated. In this semiconductor wafer, two grooves 306 and 307, which are in parallel with the repeating direction of the diffraction grating, and a mesa stripe 308 are formed. Said etching grooves have parts whose widths are different in the direction of resonant axis. A laser oscillating part is broad and noninjected region part is narrow. Then embedding growing is performed, and a P type InP current block layer 309 and the like are sequentially laminated. An N type InP current block layer 310 is provided so that it is not laminated on the upper surface of the mesa stripe 308 at the part where the width of the etching grooves is broad and laminated on the mesa stripe 308 at the part where the width of the grooves is narrow. After the crystal growth, a P type ohmic electrode 313 and an N type ohmic electrode 314 are formed. |
