| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a light modulator having low electric resistance and an excellent high frequency characteristic, and a semiconductor optical element integrating such a light modulator and semiconductor laser elements. SOLUTION: This light modulator 10 has a laminated structure on an n-InP substrate 12, consisting of an n-InP layer 14, an MQW 16 of an AlGaInAs group, a GaIn AsP layer 18, a p-InP layer 20, a p-AlInAs layer 22, a p-InP layer 24, and a p-GaInAs layer 26. The p-AlInAs layer, p-InP layer, and p-GaInAs layer are formed in striped ridges of a 10μm width. On both sides of the p-AlInAs layer, an Al-oxide layer 28, which is formed by selectively oxidizing Al in the p-AlInAs layer, extends in a width of 3.5μm from the edges of the p-AlInAs layer up to the sides of the ridge. Since the light modulator has a constricted oxide-structure permitting to widen the width of the p-clad layer up to 10μm, it has a low device resister. Moreover, since it has the constricted oxide- structure, it is little influenced by the roughness of the ridge sides and has a favorable Frequency characteristic.</p> |
