Various embodiments of the present disclosure are directed towards an amorphous bottom electrode structure (BES) for a metal-insulator-metal (MIM) capacitor. The MIM capacitor comprises a bottom electrode, an insulator layer overlying the bottom electrode, and a top electrode overlying the insulator layer. The bottom electrode comprises a crystalline BES and the amorphous BES, and the amorphous BES overlies the crystalline BES and forms a top surface of the bottom electrode. Because the amorphous BES is amorphous, instead of crystalline, a top surface of the amorphous BES may have a small roughness compared to that of the crystalline BES. Because the amorphous BES forms the top surface of the bottom electrode, the top surface of the bottom electrode may have a small roughness compared to what it would otherwise have if the crystalline BES formed the top surface. The small roughness may improve a lifespan of the MIM capacitor.