| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a semiconductor optical modulator, a Mach-Zehnder type optical modulator and an optical modulator integrated type semiconductor laser, in which an electric field is effectively applied on an optical waveguide core layer, and the propagation characteristic of a modulated wave is not deteriorated. <P>SOLUTION: An n-type clad layer 102 is stacked on a semi-insulating semiconductor substrate 101, on which an optical waveguide layer 103 is formed. The optical waveguide layer 103 is composed of clad layers 103b and 103c, and an optical waveguide core layer 103a interposed between the clad layers 103b and 103c. Further, an n-type clad layer 104 is formed on the optical waveguide layer 103. In this way, an n-type semiconductor whose electric conductivity is comparatively high, light absorptivity is comparatively low and impurities are hardly diffused, is used as the clad layers formed on and under the optical waveguide layer 103, further a semi-insulating layer is provided between the n-type clad layers 102 and 104. <P>COPYRIGHT: (C)2003,JPO</p> |
