| 摘要 |
PURPOSE:To prevent the concentration of current and improve firing sensitivity by a method wherein a low resistant buried layer provided in a base region is formed in such a way that it has a circular connecting part as a gate electrode for turning off, a principal member extending to the central part from the circular connecting part and a branch member extending to the peripheral direction from the principal member. CONSTITUTION:The horizontal shape of the low resistant buried layer of a gate turn-off thyristor consists of an external circular connecting part 6, a principal member 7 extending in the direction of the internal center at equal intervals from the connecting part 6 and a branch member 8 extended in the peripheral direction at the position of the concentric circle of the principal member 7 with the equal intervals. By this constitution, the expanding capacity of an ON-region after ignition is improved, while the concentration of current at the time of turning-off is prevented, so that a gate turn-off thyristor with improved firing sensitivity can be obtained. |
