| 摘要 |
PURPOSE:To reduce the light source noise caused by feedback lights by a method wherein a gain guide type structure with narrow stripe due to proton implantation is formed. CONSTITUTION:A first clad layer 12 is epitaxially grown and an active layer 13 is epitaxially grown on the layer 12 and a second clad layer 14 is epitaxially grown on the layer 13 and a cap layer 15 is further epitaxially grown on the layer 14. High resistance regions 16 are formed by selectively implanting proton from the surface of the side whereon the clad layer 14 is formed i.e. the surface of the cap layer 15. The high resistance regions 16 are formed on boeh sides of a stripe part with specified width W extending in one direction and the implanted ends 16a (bottom surfaces) contained in the second clad layer 14 are set up so that the distance from the active layer 13 may be 0.2-0.5mum. These proton implanted regions 16 may be selectively formed by coating the cap layer 15 with e.g. Av mask and the like and implating proton through the cap layer 15. |
