| 摘要 |
PURPOSE:To favorably inhibit a Fabry-Perot mode by contriving the exposure of only one end surface of an active layer to a laser end surface. CONSTITUTION:A diffraction grating 2 is formed on a substrate 1, and an optical layer 3, the active layer 4, a meltback prevention layer 5, and a clad layer 6 are formed thereon. Next, a mesa stripe 8 and etched grooves 7 surrounding it are formed. Current block layers 9 and 10, a buried layer 11, and an electrode layer 12 are laminated by performing burial growth to this double hetero (DH) wafer. At the time, it is contrived that only one end surface of the active layer 4 emitting light and coupling exposes to the laser end surface, and that the other end of the active layer is completely covered with the buried layer. Besides, the current block layer except for the mesa stripe is so constructed as to have a part including a semiconductor layer of the same composition as that of the active layer, and the leakage current is sufficiently reduced. |
