The present disclosure, in some embodiments, relates to a metal-insulator-metal (MIM) capacitor structure. The MIM capacitor structure includes one or more lower interconnects disposed within a lower dielectric structure over a substrate. A first dielectric layer is over the lower dielectric structure and includes sidewalls defining a plurality of openings extending through the first dielectric layer. A lower electrode is arranged along the sidewalls and over an upper surface of the first dielectric layer, a capacitor dielectric is arranged along sidewalls and an upper surface of the lower electrode, and an upper electrode is arranged along sidewalls and an upper surface of the capacitor dielectric. A spacer is along opposing outermost sidewalls of the upper electrode. The spacer has an outermost surface extending from a lowermost surface of the spacer to a top of the spacer. The outermost surface is substantially aligned with an outermost sidewall of the lower electrode.