Three-dimensional semiconductor memory device

Abstract

A semiconductor memory device includes a cell region defined with vertical channels which pass through electrode layers and interlayer dielectric layers alternately stacked; a step region disposed adjacent to the cell region in a first direction, and defined with contacts coupled to the electrode layers extending in different lengths; a first opening passing through the electrode layers and the interlayer dielectric layers in the step region; a second opening passing through the electrode layers and the interlayer dielectric layers in the cell region; under wiring lines coupled with a peripheral circuit defined on a substrate; top wiring lines disposed over the electrode layers and the interlayer dielectric layers, and coupled with the contacts; and vertical vias coupling the under and top wiring lines, wherein the vertical vias include first vertical vias which pass through the first opening and second vertical vias which pass through the second opening.