Patent ID: 11476251

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 in repeating iterations to form a vertical stack. An etchant process is used to form a first vertical opening exposing vertical sidewalls in the vertical stack adjacent a first region. The first region is selectively etched to form a first horizontal opening removing the sacrificial material a first horizontal distance back from the first vertical opening. A first source/drain material, a replacement channel material having backchannel passivation, and a second source/drain material are deposited in the first horizontal opening to form the three-node access device for a memory cell among the arrays of vertically stacked memory cells.