| 摘要 |
PURPOSE:To decrease a threshold current density and to improve a spectrum in impurity by a method wherein a distributed feedback semiconductor multilayer film is provided onto a substrate and a hetero-structure containing an active layer is formed on a side face of a step composed of the upside of the substrate and the side wall of the semiconductor multilayer film. CONSTITUTION:A semiconductor multilayer film 12 is formed on a substrate 11 so as to generate a distributed feedback. An n-type clad layer 17 of InP crystal, an active layer 18 of GnInAsP crystal, and a P-type clad layer 19 of InP crystal are successively formed on the side face of a step 16 and up to the upside of the substrate 11. The active layer 18 formed on the side wall of the step 16 emits light rays and the emitted light is reflected and amplified through a double hetero-structure, and the light rays excited by such a laser action are emitted through induction from a projecting face 21 in a direction perpendicular to the face of the substrate 11. By these processes, a threshold current density can be decreased and the spectral purity can also be improved. |
