| 摘要 |
PURPOSE:To prevent a thyristor from erroneously firing due to a discharge current from flowing to a gate electrode by forming a slit from the peripheral edge of a semiconductor substrate to an interval portion between a cathode electrode and the gate electrode. CONSTITUTION:A semiconductor substrate 1 has a semiconductor layer, a PE layer, an NB layer, a PB layer and an NE layer alternately including different conductivity types between a pair of main surfaces 101 and 102. A slit 7 is formed obliquely with respect to the radial direction of the substrate 1 on the portion 3a disposed as the peripheral side of the substrate 1 with respect to an auxiliary electrode 4 and a gate 5 of the cathode electrodes contacted via low resistance with the PB layer to surround the electrode 4, 5, and an electrode portion 3a are divided into parts 3a1, 3a2. A discharge current generated at the periphery of the substrate 1 tends to flow toward the interior of the substrate 1, but a discharge current flowing to the slit 7 flows to the portion 3a2 but does not arrive at the electrode 5. |
