| 摘要 |
PURPOSE:To reduce an ON voltage drop by commonly using parts of guard ring regions as a common region. CONSTITUTION:A first guard ring region 2 surrounding a base region 1 and a second guard ring region 11 surrounding a first emitter region 3 are commonly used at the intermediate between the regions 1 and 3 as a common region 14. When a negative potential is applied to a cathode electrode 7 and a date electrode 13 and a positive potential is applied to an anode electrode 8, a depleted layer is extended to the region of a semiconductor substrate 10 surrounding the region 1. When an applied voltage is raised, a depleted layer arrives at the region 2 surrounding the region 1. When an applied voltage is further raised, a depleted layer is extended over the region 2 to become a depleted layer region 12 to avalanche-breakdown at a predetermined voltage. The extension of the depleted layer can be suppressed by the same conventional thyristor, the same avalanche and the field plate of the region 3, resulting in suppress ion of the generation of a channel between the regions 1 and 3. |
