Interference-potential-compensated thyristor comprising at least four

Abstract

An interference-potential-compensated thyristor comprising, a common emitter zone of one conductivity type, a common main base zone of an opposite conductivity type in contact with said common emitter zone, a common control base of said one conductivity type in contact with said common main base, first and second outer emitter zones of said opposite conductivity type in contact with said common control base, a common metallized electrode layer in contact with said common emitter zone, a first opposite metallized electrode layer in contact with a portion of said common control base and said first outer emitter zone at a junction between said common control base and said first outer emitter zone, and a second opposite metallized electrode layer in contact with a portion of said common control base and said second outer emitter zone at a junction between said common control base and said second outer emitter zone, said first outer emitter zone defining a pilot thyristor part thereabout and said second outer emitter zone defining a sequential thyristor thereabout, a geometry of said first and second outer emitter zones and said first and second opposite metallized electrode layers being chosen so that a capacitance resulting from a forward blocking p-n junction and the surface resistance of said common control base result in a potential which compensates and which approximately corresponds to a maximum interference potential occurring in said common control base beneath said first outer emitter zone, and with an optical or electrical triggering, a potential develops in said common control base adjacent said portion of said first outer emitter zone in contact with said first opposite metallized electrode layer which is substantially lower than the maximum turn-on potential produced in the common control base beneath said first outer emitter zone.