LIGHT ACTIVATED THYRISTOR

摘要

The present invention pertains to a light activated thyristor which increases the current density of light-generated carriers by means of a low resistance path from an area of carrier generation in a base zone of a first conductivity type into a portion of an adjacent emitter zone of a second conductivity type. In one embodiment the low resistance path takes the form of an annular gate electrode affixed to the base zone and having a projection bordering the base-emitter PN junction. In another embodiment the low resistance path takes the form of a ballast segment disposed in the base zone, the ballast segment having an opening for funnelling the carriers to the baseemitter PN junction.