Patent attributes
A phototransistor includes a first-conduction-type lower region, a second-conduction-type upper region disposed on the first region, a second-conduction-type electrode contact region of a high concentration disposed at a surface inside of the upper region and is connected to an electrode so as to transmit a signal, a first-conduction-type first shield region of a high concentration disposed at the surface of the upper region and spaced at an interval from the electrode contact region and connected to a ground potential, and a first-conduction-type second shield region of a low concentration disposed between the electrode contact region and the first shield region at the surface of the upper region so as to surround the electrode contact region, and further, is connected to the ground potential.
