Semiconductor device

A semiconductor device, comprising:

• a semiconductor part including a first surface, a second surface, a first region provided between the first surface and the second surface, and a second region provided between the first surface and the second surface;
• a common electrode provided at the second surface, the common electrode being a metal electrode, the common electrode comprising a third surface and a fourth surface, the third surface being in contact with the second surface, the fourth surface opposing the third surface;
• a first electrode provided on the first surface at the first region;
• a second electrode provided on the first surface at the second region and separated from the first electrode;
• a first control electrode provided in the first region, the first control electrode controlling a current flowing in the first region in a direction connecting the first electrode and the common electrode;
• and
• a second control electrode provided in the second region, the second control electrode controlling a current flowing in the second region in a direction connecting the second electrode and the common electrode,
• a plurality of first trenches each extending in a first direction through the common electrode,
• the plurality of first trenches dividing the common electrode into separate sections in a second direction orthogonal to the first direction,
• the semiconductor part not being provided in the plurality of first trenches,
• a density of the plurality of first trenches in the second direction at an end portion of the device being greater than a density of the plurality first trenches in the second direction at a central portion of the device.