| 摘要 |
PROBLEM TO BE SOLVED: To enable continuous operation at a room temperature and emit and receive middle infrared rays by selecting the crystal of a substrate from a group of GaAs or a group of InP, and putting the wavelength of a laser beam in a specified range. SOLUTION: An n-InP clad layer 101 and a distorted quantum well active layer 104 consisting of GaInAs barrier layers 102 without distortion and a GaInNAs distorted well layer 103 are made in order on an n-InP substrate 100. After formation of a diffraction grating for DFB, a p-InP clad layer 105 and a p-GaInAs cap layer 106 are made. Etching is stopped in the middle of the p-InP clad layer 105 so that it may not reach the distorted quantum well active layer 104. An n-InP current narrowing layer 107 is grown selectively, and a p-GaInAs flattening layer 108 is grown again. After formation of a p-side electrode and an n-side electrode, a low reflection film, at the front of the element, and a high reflection film by four-layer film, at the rear, are made. By the above, a semiconductor laser which emits a middle infrared ray from 1.7μm to 5μm, and a light detector which receives it are obtained, and a high performance of application system can be made. |
