| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve characteristics of an electroabsorption modulator with an AlGaInAs optical absorption layer. <P>SOLUTION: An n-type InP clad layer 2, an AlGaInAs optical absorption layer 4, a p-type InGaAsP optical waveguide layer 6, and a p-type InP clad layer 7 are laminated on an n-type InP substrate 1 in this order. The p-type InGaAsP optical waveguide layer 6 has InGaAsP layers 6a, 6b, and 6c whose compositions are different one another. An energy barrier among valence bands of the InGaAsP layers 6a, 6b, and 6c is smaller compared to a case of a monolayered InGaAsP layer. <P>COPYRIGHT: (C)2012,JPO&INPIT |
