Three-dimensional semiconductor memory device, electronic system including the same

Abstract

A three-dimensional semiconductor memory device is provided. The memory device includes a substrate, a peripheral circuit structure on the substrate, and a cell array structure on the peripheral circuit structure and including a cell array region and a cell array contact region. The cell array structure includes a stack structure including alternately stacked interlayer insulating layers and gate electrodes, a first source conductive pattern, a second source conductive pattern, and a third source conductive pattern sequentially stacked on the stack structure. The first to third source conductive patterns include different materials from each other. Vertical channel structures extending into a lower portion of the first source conductive pattern through the stack structure is included. The first to third source conductive patterns extend from the cell array region to the cell array contact region. The vertical channel structures include vertical semiconductor patterns that contact to the first source conductive pattern.