A semiconductor device includes a transistor in a semiconductor body having a first main surface. The transistor includes: a source contact electrically connected to a source region; a drain contact electrically connected to a drain region; a gate electrode at the channel region, the channel region and a drift zone disposed along a first direction between the source and drain regions, the first direction being parallel to the first main surface, the channel region patterned into a ridge by adjacent gate trenches formed in the first main surface, the adjacent gate trenches spaced apart in a second direction perpendicular to the first direction, a longitudinal axis of the ridge extending in the first direction and a longitudinal axis of the gate trenches extending in the first direction; and at least one of the source and drain contacts being adjacent to a second main surface opposite the first main surface.