A semiconductor device includes a first compound semiconductor material including a first doping concentration and a second compound semiconductor material on the first compound semiconductor material, the second compound semiconductor material including a different material than the first compound semiconductor material. The semiconductor device further includes a control electrode and at least one buried semiconductor material region including a second doping concentration different from the first doping concentration. The at least one buried semiconductor material region is disposed in the first compound semiconductor material in a region other than a region of the first compound semiconductor material being covered by the control electrode.