| 摘要 |
<p>A buried-heterostructure semiconductor laser including a mesa-shaped optical confinement region having an active layer (3) and a clad layer (4) and disposed on a semiconductor substrate (1); a burying layer (6, 7) burying both side surfaces of the region; and at least one p-n junction (12) so formed inside the burying layer (6,7) in parallel to the active layer (3) as to be brought under the reversely biased state during the operation of the laser; wherein surface protection semiconductor layers (5, 8) are formed on the mesa-shaped optical confinement region and on the burying layer (6, 7), respectively, for protecting the semiconductor assembly in the arrangement such that these surface protection semiconductor layers (5, 8) do not come into direct contact with each other. Even if the forbidden band gaps of these surface protection semiconductor layers (5,8) are relatively small, it is possible to realize a semiconductor laser having an extremely small leakage current and reduced variance of threshold current values, while protecting the surface of the multi-layer semiconductor layers.</p> |
