Semiconductor memory device and method of fabricating the same

Abstract

Provided are a semiconductor memory device and a fabricating method thereof. The device includes a stack including vertical channel structures that penetrate insulating patterns and gate electrodes that are alternately and repeatedly stacked on each other. Each of the gate electrodes includes first and second gate conductive layers. In a first region between an outer side of the stack and the vertical channel structures, the first gate conductive layer is adjacent to the vertical channel structures and includes a truncated end portion, the second gate conductive layer has a portion adjacent to the vertical channel structures and covered by a corresponding one of the first gate conductive layer and an opposite portion that is not covered with the first gate conductive layer. In a second region between the vertical channel structures, the first gate conductive layer may be extended to continuously cover surfaces of the second gate conductive layer.