Patent ID: 11476254

Abstract:
Systems, methods and apparatus are provided for support pillars in vertical three-dimensional (3D) memory. An example method includes a method for forming arrays of vertically stacked memory cells, having horizontally oriented access devices and horizontally oriented storage nodes. The method includes depositing alternating layers of a dielectric material and a sacrificial material in repeating iterations to form a vertical stack. A plurality of spaced, first vertical openings are formed through the vertical stack adjacent areas where storage nodes will be formed. Support-pillar material is deposited in the plurality of spaced, first vertical openings to form structural support pillars. Second vertical openings are formed through the vertical stack adjacent the structural support pillars to define elongated vertical columns with first sidewalls of the alternating layers. A third vertical opening is formed through the vertical stack extending to expose second sidewalls adjacent areas where horizontal access devices will be formed. The sacrificial material is selectively etched to form first horizontal openings, removing the sacrificial material a first horizontal distance (D1) back from the third vertical opening. A fourth vertical opening is formed through the vertical stack to expose third sidewalls adjacent areas where storage nodes will be formed. The support-pillar material of the formed structural support pillars may serve as an etch stop in selectively etching to form the second horizontal openings.