A semiconductor device is disclosed. A semiconductor device according to an example of the present disclosure includes a gate electrode of a ring shape having an opening area on a substrate; a P-type deep well region formed in the opening area; a drain region formed on the P-type deep well region; an N-type well region overlapping with the gate electrode; a source region formed in the N-type well region; a bulk tab region formed by being isolated from the source region by a first isolation region; a P-type drift region formed in contact with the N-type well region; and a second isolation region formed near the bulk tab region.