The application relates to a semiconductor die having a semiconductor body including an active region, an insulation layer on the semiconductor body, and a sodium stopper formed in the insulation layer. The sodium stopper is arranged in an insulation layer groove which intersects the insulation layer vertically and extends around the active region. The sodium stopper is formed of a tungsten material that at least partly fills the insulation layer groove. Both the insulation layer groove and the tungsten material extend into the semiconductor body.