| 摘要 |
<p>PURPOSE:To provide a semiconductor laser characterized by a low oscillation threshold current and high differential quantum efficiency, by providing an optical waveguide in an output region, thereby improving the feedback rate between an active layer and the output region. CONSTITUTION:A positive voltage is applied to a P side electrode 19 and a negative voltage is applied to an N side electrode 20. Carriers are injected only to an active layer 16 by P-N reverse bias of epitaxial layers 10, 11, and 12. Light emission is obtained by recombination. The carriers injected into the active layer 16 are completely confined in the active layer 16 by clad layers 15 and 17, respectively. The laser light generated by the active layer 16 is guided by the clad layers 15 and 17 whose refractive index is low, and combined to the epitaxial layers 10, 11, and 12. The light guided into the active layer 16 is again guided into the core layer 11 by the clad layers 10 and 12, and resonated between cleavage planes. By forming the core layer 11 and the clad layers 10 and 12 at first, the flat waveguide, wherein the interface between the core layer and the clad layers has small uneven parts, is formed.</p> |
