| 摘要 |
PURPOSE:To obtain a semiconductor laser device whose manufacturing process is simplified, whose yield of an element is enhanced, whose coupling coefficient between a beam and a diffraction grating is large and which is oscillated satisfactorily in single longitudinal mode by a method wherein a semiconductor laser device having the diffraction grating is formed by two crystal growth processes using a vapor crystal growth method. CONSTITUTION:A first semiconductor layer 2 of a first conductivity type, a second semiconductor layer 3 of the first conductivity type to be used as a laser active layer and a third semiconductor layer 4 of a second conductivity type to be used as a laser waveguide layer are epitaxially grown one after another on a compound semiconductor substrate 1 of the first conductivity type. Then, the surface of the layer 4 is etched selectively in order to form a diffraction grating 5; the layers 2-4 are etched selectively down to at least the layer 2 in a direction perpendicular to grooves of the diffraction grating 5 in order to form a stripe-shaped laser resonator structure 6. Then, a fourth semiconductor layer 7 of the second conductivity type and a fifth semiconductor layer 8 of the first conductivity type are epitaxially grown by a vapor crystal growth method. After that, a first impurity to be used as the second conductivity type is diffused 9 onto an upper part of the laser resonator structure 6 from the surface of the layer 8 down to at least the layer 7. |
