Some embodiments relate to a method for forming a memory device. The method includes forming a lower dielectric layer over a conductive wire. A stack of memory layers is formed within the lower dielectric layer and over the conductive wire. The stack of memory layers comprises a top electrode, a bottom electrode, and a data storage layer between the top electrode and the bottom electrode. A removal process is performed on the stack of memory layers to define a programmable metallization cell that comprises the top electrode, the bottom electrode, and the data storage layer. The programmable metallization cell comprises a central region and a peripheral region that extends upwardly from the central region. A top surface of the programmable metallization cell and a top surface of the lower dielectric layer are coplanar.