| 摘要 |
In the present invention, a first trench (5a) and a second trench (5b) form a trench (5) that is deeper than the width of a p base layer (4), and the second trench (5b), which is located in the lower part of the trench (5), is formed by a third trench (5c) and a fourth trench (5d). The width of the second trench (5b) in the X direction is greater than that of the first trench (5a) located in the upper part of the second trench (5b). Furthermore, in the X direction the degree of widening of the second trench (5b) differs for the third trench (5c) and the fourth trench (5d). Thus, the width of the lower part of the trench can be made to differ in the Y direction, enabling the gate capacity to be made smaller than when the lower part uniformly widens in the length direction of the trench (5). Furthermore, the ON voltage can be reduced, and the switching tolerance can be improved. |
