US Patent 11910734 Phase change memory cell with ovonic threshold switch

A structure including a bottom electrode, a phase change material layer vertically aligned and an ovonic threshold switching layer vertically aligned above the phase change material layer. A structure including a bottom electrode, a phase change material layer and an ovonic threshold switching layer vertically aligned above the phase change material layer, and a first barrier layer physically separating the ovonic threshold switching layer from a top electrode. A method including forming a structure including a liner vertically aligned above a first barrier layer, the first barrier layer vertically aligned above a phase change material layer, the phase change material layer vertically aligned above a bottom electrode, forming a dielectric surrounding the structure, and forming an ovonic threshold switching layer on the first barrier layer, vertical side surfaces of the first buffer layer are vertically aligned with the first buffer layer, the phase change material layer and the bottom electrode.