| 摘要 |
PURPOSE:To oscillate constantly a fundamental horizontal mode only by a method wherein layers such as the p type first clad layer and an n type light guide layer are piled successively, an effective refractive index difference is provided and an oscillated light wave is guided. CONSTITUTION:After an n<->GaAs laye 16 is grown on a p<->GaAs substrate 11, a V-shaped concave 10 is formed and the concave is etched in such a manner that the tip of the concave reaches the substrate 11. On the substrate 11 the first clad layer 13, the second clad layer 20, an activated layer 12, a light guide layer 21, the third clad layer 14 and a cap layer 17 are piled successively by a continuous liquid phase growing method. The thickness of the layers mentioned above are controlled in such a manner that the growth of the layer 13 stopped before the V-shaped concave becomes flat and after the growth of the layer 20 the concave becomes flat. With above method the thickness of the layer 20 is the largest at the center of the concave and the layer 20 has the distribution of the thikncess along the horizontal direction. Then an Al crystal mixing ratio is taken large enough and the refractive index difference between the layer 13 and the layer 12 is taken large enough, so that the leakage of the guided light wave into the current limiting layer 16 is eliminated. |
