Three-dimensional memory devices and fabricating methods thereof

Abstract

The present disclosure provides a method for forming a three-dimensional memory device. The method can comprise forming a film stack with a plurality of dielectric layer pairs on a substrate, forming a channel structure region in the film stack including a plurality of channel structures, and forming a first staircase structure in a first staircase region and a second staircase structure in a second staircase region. Each of the first staircase structure and the second staircase structure can include a plurality of division block structures arranged along a first direction. A first vertical offset defines a boundary between adjacent division block structures. Each division block structure includes a plurality of staircases arranged along a second direction that is different from the first direction. Each staircase includes a plurality of steps arranged along the first direction.