| 摘要 |
PURPOSE:To enable the lateral mode stable over regions to a high-current injected region to be obtained by cutting off the high-degree lateral mode in a laser oscillation region by a method wherein a buried layer to adjust the difference in refractive index in the horizontal direction is formed in the junction plane on both sides the laser oscillation region with a curved active layer. CONSTITUTION:A mesa stripe 28 having a width almost equal to a waveguid width Wg1 or smaller than it is formed by removing both sides of the laser oscillation operating region. The difference in refractive index in the lateral direction is reduced by filling both sides of this stripe with GaAlAs layers 27, 27. Then, the Al mixed crystal ratio of the buried layer 27 us optimized with the curving degree of the active layer 24, thereby making the difference in refractive index with good reproducibility. As a result, laser oscillation occurs in the curved part 28, and the basic lateral mode stable over regions to a high-current injected region can be obtained. It follows that laser beams only pass through the flat window region of the active layer 24. This construction cuts off the high-degree lateral mode in the laser oscillation region and then yields the basic lateral mode stable over regions to a high-current injected region and the high output for strength against end-surface breakdown. |
