Thyristor with segmented turn-on line for directing turn-on current

摘要

A thyristor with a segmented turn-on line is provided in which portions of the turn-on line are covered by boundary shorts formed by the emitter electrode extending over the emitter-base junction into contact with the thyristor base zone. The portions of the emitter-base junction between the boundary shorts constitute turn-on segments along which gated thyristor turn-on can occur. A gate current source is provided for supplying carriers to the base zone. The thyristor includes means for directing carriers supplied by the gate current source to the turn-on segments. In operation, initial thyristor turn-on occurs only along the turn-on segments, thereby shortening the length of the thyristor turn-on line and increasing gate sensitivity. Preferably, the turn-on segments are spaced regularly along the emitter-base junction to permit adjacent "on" areas to rapidly merge. In the preferred embodiment, the means for directing carriers to the turn-on segments includes a gate barrier region adjacent the base zone and of opposite conductivity type. The gate barrier region establishes isolated areas of contact between a gate electrode and the base, the areas of contact being generally aligned with the turn-on segments.