| 摘要 |
PURPOSE:To prevent deterioration in monitoring sensitivity, by using the same epitaxial crystal as an active layer and a photodetector for laser, and enhancing the dimensions for confining the quantum of the active layer of the laser higher than the dimensions of the quantum of the photodetector. CONSTITUTION:On an n-GaAs substrate 1, an n-Ga0.5Al0.5As clad layer 2 and non-doped GaAs/Ga0.8Al0.2As super-lattice active layer 10 are grown. A line and space pattern is formed in the direction of a resonator only at a part corresponding to the active layer 10 for laser by using an electron beam lithography method. The pattern is transferred to the super-lattice by a dry etching method, and a thin quantum line is formed. After the resist is removed, the thin quantum line of the super-lattice is embedded with Ga0.8Al0.2As, and a Ga0.5Al0.5As clad layer 4 and a p-GaAs cap 5 are grown. After electrodes 6, 8 and 9 are formed, a groove 7, which electrically isolates a laser part and a light receiving part, is formed. Thus a monolithic integrated circuit, which can monitor the oscillating intensity of the thin quantum line laser, can be obtained. |
