A vertical semiconductor device comprises a semiconductor body, a first contact and a second contact, wherein a first semiconductor region of a first conductivity type, a second semiconductor region of a second conductivity type and a third semiconductor region of a second conductivity type are formed in the semiconductor body in a direction from the first contact to the second contact, wherein a basic doping density of the second semiconductor region is smaller than a doping density of the third semiconductor region, and wherein in the second semiconductor region a semiconductor zone of the second conductivity type is arranged in which the doping density is increased relative to the basic doping density of the second semiconductor region.