There is provided a peripheral circuit region including a plurality of circuit elements disposed on a first substrate; and a cell region including at least one channel region extending from an upper surface of a second substrate disposed on the first substrate in a direction perpendicular to the upper surface of the second substrate, and a plurality of gate electrode layers and a plurality of insulating layers stacked on the second substrate to be adjacent to the at least one channel region, wherein at least a portion of the first substrate contacts the second substrate, and the first substrate and the second substrate provide a single substrate.