US Patent 11227872 FeRAM MFM structure with selective electrode etch

In some embodiments, the present disclosure relates to an integrated chip including one or more lower interconnect layers arranged within one or more stacked inter-layer dielectric layers over a substrate. A bottom electrode is disposed over the one or more interconnect layers, and a top electrode is disposed over the bottom electrode. A ferroelectric layer is disposed between and contacts a first surface of the bottom electrode and a second surface of the top electrode. The ferroelectric layer includes a protrusion that extends past outer surfaces of the top electrode and the bottom electrode along a first direction that is perpendicular to a second direction that is normal to the first surface. The protrusion is confined between lines that extend along the first and second surface.