Micron Technology, Inc.
Replacement gate dielectric in three-node access device formation for vertical three dimensional (3D) memory

Abstract:

Systems, methods, and apparatus are provided for storage node after horizontally oriented, three-node access device formation 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 semiconductor material to form a vertical stack. A first vertical opening is formed through the vertical stack to expose a first region of the sacrificial semiconductor material. The first region is selectively removed to form a first horizontal opening in which to replace a sacrificial gate dielectric material, form a source/drain conductive contact material, a channel conductive material, and a digit line conductive contact material of the three-node access device.