Micron Technology, Inc.
Gate dielectric repair on three-node access device formation for vertical three-dimensional (3D) memory

Abstract:

Systems, methods and apparatus are provided for a three-node access device 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 vertically oriented access lines. The method includes depositing alternating layers of a dielectric material and a sacrificial material to form a vertical stack. Forming a plurality of first vertical openings to form elongated vertical, pillar columns with sidewalls in the vertical stack. Conformally depositing a gate dielectric in the plurality of first vertical openings. Forming a conductive material on the gate dielectric. Removing portions of the conductive material to form a plurality of separate, vertical access lines. Repairing a first side of the gate dielectric exposed where the conductive material was removed. Forming a second vertical opening to expose sidewalls adjacent a first region of the sacrificial material. Selectively removing the sacrificial material in the first region to form first horizontal openings. Repairing a second side of the gate dielectric exposed where the sacrificial material was removed in the first region. Depositing a first source/drain region, a channel region, and a second source/drain region in the first horizontal openings.