| 摘要 |
PURPOSE:To obtain a gate turn-off thyristor (GTO) having a gate electrode structure suitable for the improvement of a breaking strength by a method wherein plural pieces of ring-shaped gate current collecting electrode plates are provided in such a way as to adjoin each of the multiple rings of cathode emitter layers arranged on a circular semiconductor substrate and a plurality of regions extended radially to the periphery of the substrate from its central part are provided in such a way that the gate current collecting electrode plates are mutually coupled with a gate electrode. CONSTITUTION:N-type cathode emitter layers 2 are arranged on a circular semiconductor substrate 1 in a sextuple ring-shaped radial form and a gate electrode is provides on a P-type cathode base layer to be exposed on their peripheries in such a way as to encircle the layers 2. The gate electrode has ring-shaped gate current collecting electrode plates 10 adjacent to each ring of the layers 2, regions 11 extended radially to the periphery part of the substrate 1 from its central part in such a way that the electrode plates 10 are mutually coupled with the gate electrode and a gate current collecting electrode plate 12 on the central part of the substrate. According to this structure, the resistance of the gate electrode can be uniformized in the whole within the surface of a large-diameter GTO element. Therefore, as the numerous unit GTOs are operated uniformly, the breaking strength can be improved. |
