Semiconductor memory device, method of fabricating the same, and electronic system including the same

Abstract

Provided are a memory device, a method of fabricating the same, and an electronic system including the same. The memory device includes a peripheral circuit structure and a cell structure on the peripheral circuit structure. The cell structure comprises a cell substrate including a first surface facing the peripheral circuit structure and a second surface opposite to the first surface and having a first conductivity type, gate electrodes on the first surface of the cell substrate, a channel structure intersecting the gate electrodes and connected to the cell substrate, a first impurity region that is in the cell substrate adjacent to the second surface and has a second conductivity type, and a second impurity region that is in the cell substrate and is spaced apart from the first impurity region, the second impurity region having the first conductivity type with a higher impurity concentration than that of the cell substrate.