Semiconductor device

A semiconductor device comprising:

• a semiconductor layer having a first plane and a second plane;
• a first semiconductor region of a first conductivity-type provided in the semiconductor layer;
• a second semiconductor region of a second conductivity-type provided in the semiconductor layer, and the second semiconductor region located between the first semiconductor region and the first plane;
• a third semiconductor region of the first conductivity-type provided in the semiconductor layer, the third semiconductor region located between the second semiconductor region and the first plane, and the third semiconductor region having a lower first conductivity-type impurity concentration than the first semiconductor region;
• a fourth semiconductor region of the second conductivity-type provided in the semiconductor layer, the fourth semiconductor region located between the third semiconductor region and the first plane, and the fourth semiconductor region having a higher second conductivity-type impurity concentration than the second semiconductor region;
• a fifth semiconductor region of the first conductivity-type provided in the semiconductor layer, the fifth semiconductor region provided between the first semiconductor region and the first plane, and the second semiconductor region being interposed between the fifth semiconductor region and the third semiconductor region;
• a first electrode provided on a side of the first plane of the semiconductor layer, and the first electrode electrically connected to the third semiconductor region and the fourth semiconductor region;
• a second electrode provided on a side of the second plane of the semiconductor layer, and the second electrode electrically connected to the first semiconductor region;
• and
• a conductive layer provided on a side of the first plane of the semiconductor layer, and the conductive layer electrically connecting the second semiconductor region and the fifth semiconductor region.