Various embodiments of the present application are directed towards a metal-insulator-metal (MIM) capacitor. The MIM capacitor comprises a bottom electrode disposed over a semiconductor substrate. A top electrode is disposed over and overlies the bottom electrode. A capacitor insulator structure is disposed between the bottom electrode and the top electrode. The capacitor insulator structure comprises at least three dielectric structures vertically stacked upon each other. A bottom half of the capacitor insulator structure is a mirror image of a top half of the capacitor insulator structure in terms of dielectric materials of the dielectric structures.