A semiconductor device includes a semiconductor body having a semiconductor body material with a dopant diffusion coefficient that is smaller than the corresponding dopant diffusion coefficient of silicon, at least one first semiconductor region doped with dopants of a first conductivity type and having a columnar shape that extends into the semiconductor body along an extension direction, wherein a respective width of the at least one first semiconductor region continuously increases along the extension direction; and at least one second semiconductor region included in the semiconductor body. The at least one second semiconductor region is arranged adjacent to the at least one first semiconductor region, and is doped with dopants of a second conductivity type complementary to the first conductivity type.