| 摘要 |
PURPOSE:To perform a stable single lateral mode oscillation and enable to readily control a semiconductor laser by providing a double hetero structure formed of upper and lower stages of steps of stair made of the prescribed semiconductor layer and the prescribed clad layers on the side. CONSTITUTION:Steps of a stair which includes a double hetero structure formed of the first semiconductor layer 50, the second semiconductor layer 60 and the third semiconductor layer 70 is provided on a semiconductor substrate 10. The forbidden band widths of the first and third semiconductor layers 50, 70 formed in the double hetero structure are not larger than that of the active layer 20, and the forbidden band width of the layer 60 is larger than that of the layer 20. The double hetero structure for the laser formed of the first clad layer, the active layer and the second layer is provided on the bottom, upper and side of the steps on the stair. The laser light emitting range at this time becomes the layer 20 on the side of the step of the stair, and single lateral mode oscillation occurs. Thus, stable single lateral mode oscillation is performed, and can be readily controlled. |
