| 摘要 |
PURPOSE:To enable to efficiently turn a thyristor device to OFF even at a time when the anode current is a larger quantity of current by method wherein the OFF-gain is increased without increasing the ON-gain by making smaller the current amplification hFE of the N-P-N type transistor of the thyristor than the hFE of the N-P-N type transistor thereof for turn-OFF. CONSTITUTION:The thyristor is made in a P-N-P-N type four-layer structure consisting of a P type region 112, an N type region 104, a P typre region 108 and an N type region 114. A P-N-P type transistor T0 is formed of the regions 112, 104 and 108 and an N-P-N type transistor T1 is formed of the regions 104, 108 and 114, while an N-P-N type transistor T2 for turn-OFF is formed of the region 114, a P type region 110 and an N type region 106. The P type impurity concentration of the base region 108 of the N-P-N type transistor T1 is formed in such a way as to become higher than that of the base region 110 os the transistor T2 for turn-OFF. As a result, the current amplification hFE of the N-P-N type transistor T1 can be made smaller than the hFE of the N-P-N type transistor T2 for turn-OFF. |
