SEMICONDUCTOR DEVICE AND METHOD OF MANUFACTURING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a technology for further improving withstanding voltage characteristics, in a semiconductor device having a semiconductor region that facilitates extension of a depletion layer at a side part and a bottom part of a trench.SOLUTION: Provided is a semiconductor device having a gate insulating layer and a gate electrode in a trench. A step is formed on a lateral face of the trench. The lateral face of the trench has an upper lateral face and a lower lateral face. The surface of the step is inclined so as to be displaced downward as it goes to the center side of the trench. The semiconductor substrate has: a first region of a first conductivity type contacted with the gate insulating layer at the upper lateral face; a body region of a second conductivity type contacted with the gate insulating layer at the upper lateral face at a lower side in the first region; a second region of the first conductivity type contacted with the gate insulating layer at the upper lateral face and the lower lateral face at a lower side of the body region; a side region of the second conductivity type contacted with the gate insulating layer at the lower lateral face; and a bottom region of the second conductivity type contacted with the gate insulating layer at a bottom face of the trench.SELECTED DRAWING: Figure 2