| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor device such as a PT-type reverse blocking IGBT including a thin drift region where a reverse withstand voltage equivalent to a forward withstand voltage is secured, and to provide a method for manufacturing it. SOLUTION: A second trench groove 22 is formed on a collector electrode 25 side. The surface of the second trench groove 22 is coated with an oxide film 23, and filled with polysilicon 24. A second n-buffer region 17 is formed at a point sandwiched between the second trench grooves 22. A depletion layer at reverse bias extends to an n<SP>-</SP>drift region 19 over the second n-buffer region 17. Thereby the reverse breakdown voltage equivalent to the forward breakdown voltage is acquired in a PT-type structure. COPYRIGHT: (C)2004,JPO |
