INSULATED GATE BIPOLAR TRANSISTOR

摘要

PROBLEM TO BE SOLVED: To provide an IGBT (insulated gate bipolar transistor) where latch-up breakage occurs hardly. SOLUTION: In a cell region, a dummy trench 23 is formed adjacently to an active trench 10. In a peripheral region, two p+-layers 15 are formed from under the surface of a channel p region 6a, and a RESURF p layer 16 is formed outside of it. The p+-layers 15 project to inside of an n--layer 5, and an electric field around the p+-layers 15 can be intensified, so that breakdown voltage at a Zener diode structure of pn junction composed of the p+-layers 15 and the n--layer 5 can be dropped to be lower than the breakdown voltage in the cell region. Furthermore, a part composed of the p+-layers 15, the n--layer 5, an FS layer 4 and a p+-layer 3 has a pnp transistor structure. Thus, in the case of breakdown of the IGBT 1, the part of the pnp transistor structure starts breakdown earlier than the cell region due to the breakdown characteristic of a pnp transistor, so that the IGBT where latch-up breakage occurs hardly is obtained. COPYRIGHT: (C)2008,JPO&INPIT