Semiconductor device

A semiconductor device, comprising:

• a support body including a first surface;
• a first conductive part, a direction from the first surface toward the first conductive part being along a first direction perpendicular to the first surface;
• a second conductive part separated from the first conductive part in a second direction along the first surface;
• a semiconductor layer including a first end surface, a second end surface, a counter region, and a first semiconductor region, the first end surface being positioned between the first conductive part and the second conductive part, the second end surface being positioned between the first end surface and the support body, the first semiconductor region being of a first conductivity type, the counter region being positioned between the second conductive part and the first semiconductor region and facing a portion of the second conductive part;
• a third conductive part separated from the counter region and a portion of the second conductive part in a third direction, the third direction crossing the second direction and being along the first surface;
• and
• a fourth conductive part separated from the first semiconductor region in the third direction,
• the first semiconductor region including
• a first upper end region including a portion of the first end surface,
• a first lower end region including a portion of the second end surface, and
• a first intermediate region positioned between the first upper end region and the first lower end region,
• a first-conductivity-type impurity concentration in the first upper end region being greater than a first-conductivity-type impurity concentration in the first intermediate region,
• a first-conductivity-type impurity concentration in the first lower end region being greater than the first-conductivity-type impurity concentration in the first intermediate region.