SEMICONDUCTOR DEVICE

A semiconductor device is provided. The semiconductor device includes: a lower structure including a bit line; a cell semiconductor body vertically overlapping the bit line, on the lower structure; a peripheral semiconductor body including a portion disposed on a same level as at least a portion of the cell semiconductor body, on the lower structure; and a peripheral gate on the peripheral semiconductor body, wherein the peripheral semiconductor body includes a lower region having a first width and an upper region having a second width, greater than the first width on the lower region.