| 摘要 |
PROBLEM TO BE SOLVED: To achieve both a high-speed operation and improvement in withstanding voltage.SOLUTION: In a structure in Fig. 1, an oxide film 26 is formed to be uniformly thin on a lateral face where a gate electrode 27 is formed and to be thick at a bottom face center side of a groove 24. In this structure, the gate electrode 27 is not formed at the bottom face side of the groove 24, and is divided into both sides, and a bottom face electrode 28 is made to have the same potential as an emitter electrode 30. Thereby, a feedback capacity is reduced. In the above configuration, because a capacity between the emitter electrode 30 and a collector electrode 31 is also reduced, an output capacity Coes can be reduced. Further, the gate electrode 27 is formed to a position where the oxide film 26 is thinned at the bottom part. Therefore, the oxide film 26 between the gate electrode 27 and the bottom face of the groove 24 becomes thin, and thereby, a depletion layer immediately under the oxide film 26 becomes thick. |
