| 摘要 |
A semiconductor device includes: a semiconductor layer of a first conductivity type; a plurality of first semiconductor pillar regions of the first conductivity type provided on a major surface of the semiconductor layer; a plurality of second semiconductor pillar regions of a second conductivity type being adjacent to the first semiconductor pillar regions; a first main electrode provided on a side opposite to the major surface of the semiconductor layer; a first semiconductor region of the second conductivity type provided on the second semiconductor pillar regions; a second semiconductor region of the first conductivity type provided in a surface portion of the first semiconductor region; a second main electrode provided on the second semiconductor region; a trench being adjacent to the first semiconductor region and the second semiconductor region and reaching the first semiconductor pillar region from the surface side of the second semiconductor region; an insulating film provided on an inner wall surface of the trench; and a control electrode buried inside the trench via the insulating film. The doping concentration in the vertical direction at the center of the width of the second semiconductor pillar region is substantially constant up to a substantially intermediate portion in the direction from the second main electrode toward the first main electrode and gradually decreases from the substantially intermediate portion toward the first main electrode. |
