An embodiment semiconductor device includes a conductive region extending in a first direction and a second direction intersecting the first direction and stacked in a third direction intersecting the first direction and the second direction and a termination region at an end of the conductive region in the first direction, wherein the termination region includes an n+ type substrate, an n− type layer disposed on an upper surface of the n+ type substrate and having a plurality of first trenches opening upward in the third direction, and a lower gate runner covering the plurality of first trenches and disposed on an upper surface of the n− type layer.