| 摘要 |
<p>PURPOSE:To enhance a linearity and a temperature characteristic of an optical-output monitoring efficiency by forming a layer structure where a region used as a semiconductor laser is constituted while a double heterostructure is sandwiched between two grooves and a region used as a photodiode is formed in such a way that the double heterostructure is filled by a current-blocking layer. CONSTITUTION:A layer structure of a laser part 1 is formed in the following way: an active layer and a clad layer 5 are laminated on a substrate 3; after that, an etching operation is executed; the active layer is divided into a first stripe-shaped active layer 6 and a second active layer 7; a current-blocking layer 8 constituted of three layers is formed; lastly, a cap layer 9 is formed. On the other hand, a layer structure of a photodiode part is formed in the following way: the active layer and the clad layer 5 are laminated; the current-blocking layer 8 and the cap layer 9 are formed on both sides and at the upper part of the first active layer 6. As a result, a temperature dependence of a leakage current of an injected current is small in the laser part 1; the temperature dependence of a laser oscillation characteristic is small; in the photodiode part 2, a laser is hardly subjected to a natural radiant beam and a scattered beam. Thereby, it is possible to obtain a device whose linearity and temperature characteristic of an optical-output monitoring efficiency are excellent.</p> |
