| 摘要 |
<p>PURPOSE:To form a multiplex quantum well optical modulator with high optical performance by specifying the ranges of the Al composition of InGaAlAs and the thickness of its one layer. CONSTITUTION:On an n<+>-InP substrate 3, an n-InAlAs layer 4 is formed and then a barrier layer consisting of an InGaAlAs well layer 1 and an InAlAs layer is laminated alternately in order by, for example, a molecular beam epitaxial method, etc., to form a multiple quantum well structure(MQW) layer 5. On this MQW layer 5, a p<+>-InAlAs layer 6 and a p<+>-InGaAs layer 7 for contacting are further formed successively. At this time, the Al composition of InGaAlAs is set to 0.7-7% and the thickness of its one layer is set to 70-140Angstrom . Consequently, the electric field effect of the exciter absorption of the multiple quantum well structure is large and a high extinction ratio is realized with a low applied voltage.</p> |
