| 摘要 |
PURPOSE:To enable one oscillated light to be led out from a plurality of waveguide paths by forming a ridge portion and groove portions adjacently to each other on the surface of the substrate made of a material having a wider forbidden band width and a small reflactive index than those of the active layer. CONSTITUTION:A ridge portion 8' and grooves 9 are formed on the surface of an N type substrate 8. Used as the material for the substrate 8 is one having a wider forbidden band width and a smaller reflactive index than those of the active layer 10 to be grown thereon. On said substrate 8, an active layer 10, a P type clad layer 11 and an N type electrode forming layer 12 are successively grown. Then, zince is diffused from the layer 12 directly above the ridge portion 8' until reaching the layer 11 in order to form a P type diffused layer 13. Then, the crytal directly above the groove portions 9 is removed so that the layer 10 is exposed, and a P-side ohmic electrode 15 is formed. After an N-side ohmic electrode 17 has been formed on the substrate 8, rectifying elecrodes are formed on the groove portions. Now, when a forward bias is applied between alpha-beta, the laser oscillation occurs at the active layer above the ridge portion 8'. The groove portions 9 form optical waveguide paths, and by applying a voltage between beta-gamma, the intensity of the laser beam can be modulated. |
