Provided are semiconductor devices having a three-dimensional stacked structure and methods of manufacturing the same. A semiconductor device includes a plurality of channel structures on a substrate and arranged in a three-dimensional array; a plurality of gate electrodes extending in a direction parallel to the substrate; and a plurality of source and drain electrodes extending in a direction perpendicular to the substrate. The gate electrodes are connected to the channel structures arranged in the direction parallel to the substrate, and the source and drain electrodes are connected to the channel structures arranged in the direction perpendicular to the substrate. The channel structures include a channel layer and a ferroelectric layer on the channel layer.