Provided are semiconductor devices including a peripheral region and a cell region stacked thereon and a method of fabricating the same. The semiconductor device may include a peripheral region including a lower substrate and a peripheral circuit provided thereon and a cell region including an upper substrate and a cell array provided thereon. The cell region may be stacked on the peripheral region. When an operation signal is applied to the cell region from the peripheral region, at least a portion of the peripheral and cell regions may be used as a ground pattern applied with a ground signal, thereby being in an electrical ground state.