| 摘要 |
<p>A semiconductor laser device comprises at least an optical confinement region constituted by first, second, third and fourth semiconductor layers (2...5) provided on the upper part of a predetermined semiconductor substrate (1) in contact with each other successively, the first and fourth semiconductor layers (2, 5) being smaller in refractive index than the second and third semiconductor layers (3, 4), the third semiconductor layer (4) being larger in refractive index than the second semiconductor layer (3), the second and fourth semiconductor layers (3, 5) being larger in forbidden band width than the third semiconductor layer (4) and at least the first and fourth semiconductor layers (2, 5) being opposite in conductivity type to each other. The optical confinement region is formed into a mesa-stripe, both side walls of which substantially parallel to the traveling direction of a laser beam are embedded with a fifth semiconductor layer (7, 8), and the width of the second semiconductor layer (3) in a section perpendicular to the traveling direction of the laser beam and in the direction parallel to a junction within the optical confinement region is made larger than that of the third semiconductor layer (4). A large output is ensured by this semiconductor laser device.</p> |
