| 摘要 |
PURPOSE:To obtain a laser device, working currents therefor are small, by projecting a pair of parallel ridges from the surface of a semiconductor substrate, superposing a clad layer and an active layer and oscillating the device at a single mode. CONSTITUTION:An N type GaAs substrate 1 is etched selectively to form two strips of parallel ridges 1a, 1b. An N-Ga1-xAlxAs clad 2, a Ga1-yAlyAs active layer 3, a P- Ga1-xAlxAs clad 4 and P-GaAs 5 are grown through a liquid phase epitaxial method. Sections in the vicinity of the outer side surfaces of a ridge pair are shaped thickly in the growth rate of the clad layer 2 at that time because a growth rate thereof is remarkably large on the side surfaces of the ridges. Consequently, when the active layer 3 is superposed, the growth rate is increased on the inclined plane sections of the layer 2, and the sections in the vicinity of the outsides of the ridge pair are formed thickly. When an electrode is attached to an upper section corresponding to a groove between the ridges, conducted and light-emitted, light is absorbed in the section of the clad layer on the top surfaces of the ridges because the clad layer on the top surfaces of the ridges is thin, the spreading of currents is inhibited effectively because the clad and active layers are thick on the outsides of the ridge pair, light emission is limited in an extremely narrow region, the titled device oscillates at a single mode, and working currents are also reduced. |
