Patent ID: 8861266

Claim:
A method for operating a phase change memory, the method comprising: initializing a memory cell, the memory cell comprising a first conductive electrode having a length greater than a width of the first conductive electrode and an axis aligned with the length, wherein the first conductive electrode is a plated trench wall of a first trench aligned parallel to the length, a second conductive electrode having an edge oriented at an angle to the axis of the first conductive electrode, an insulator providing a separation distance between an end of the first conductive electrode and the edge of the second conductive electrode, and a phase change material covering a substantial portion of the first conductive electrode and at least a portion of the second conductive electrode, the initializing comprising: creating a first amorphous material region in the phase change material, the first amorphous material region covering a substantial area of the phase change material; creating an active crystalline material region inside the first amorphous material region by crystallizing a portion of the first amorphous material region; and storing information in the memory cell by creating a second amorphous material region inside the active crystalline material region while the active crystalline material region is inside the first amorphous material region; wherein the second conductive electrode is in a second trench perpendicular to the first trench; and wherein the insulator is formed on a bottom surface and sidewalls in the second trench, the insulator being formed underneath the second conductive electrode and on sides of the second conductive electrode; wherein an intersection is formed by the first conductive electrode, the insulator on one of the sidewalls of the second trench, and the second conductive electrode in the second trench; and wherein the phase change material is on top of the intersection.