| 摘要 |
PURPOSE:To improve the switching characteristics by laminating a semiconductor clad layer and a semiconductor waveguide layer of the same conduction type on an uniconduction type semiconductor substrate, forming two rib type optical waveguides closely thereupon, and providing a high resistance layer between those two rib type optical waveguides. CONSTITUTION:The 1st semiconductor clad layer 102 and semiconductor waveguide layer 103 of the same conduction type are laminated in order on the uniconduction type semiconductor substrate 101 and two rib type optical waveguides consisting of 2nd semiconductor clad layers 104 and semiconductor cap layers 105 of opposite conduction types are formed thereupon. Then the high resistance layer 109 is provided between those two rib type optical waveguides. At this time, the two optical waveguides are electrically independent of each other, so even when one electrode 106a (106b) is applied with a voltage, its influence does not extent and the other electrode 106b (106a) need not be short-circuited to an electrode 107 on the side of the substrate 101. Consequently, no current flows between the electrodes 106a and 106b and the switching characteristics can be improved. |
