Photo semiconductor device having a multi-quantum well structure

摘要

A multi-quantum well structure which is formed by laminating thin semiconductor layers is provided with means for injecting carriers in a direction which is parallel to the surface of the laminated thin semiconductor layers, whereby it is possible to obtain satisfactory changes in refractive index of the carrier injection portion. For example, if the total reflection region of an optical switch consisting of optical waveguides which cross each other is provided with a multi-quantum well structure wherein carriers are injected in a direction parallel to the surface of the well, the extinction ratio characteristics of the device can be improved.