US Patent 7943420 Single mask adder phase change memory element

A method of fabricating a phase change memory element within a semiconductor structure and a semiconductor structure having the same that includes etching an opening to an upper surface of a bottom electrode, the opening being formed of a height equal to a height of a metal region formed within a dielectric layer at a same layer within the semiconductor structure, depositing a conformal film within the opening and recessing the conformal film to expose the upper surface of the bottom electrode, depositing phase change material within the opening, recessing the phase change material within the opening, and forming a top electrode on the recessed phase change material.