The antifuse structure of the present invention includes a bottom planarized electrode, an ILD disposed over the bottom electrode, an antifuse cell opening in and through the ILD exposing the bottom electrode, a first barrier metal layer disposed in the antifuse cell opening to protect the antifuse material layer from diffusion from the bottom electrode and to form an effective bottom electrode of reduced area, hence reducing the capacitance of the device, an antifuse material layer disposed in the antifuse cell opening and over the first barrier metal layer, a second barrier metal layer disposed over the antifuse material layer, and a top electrode disposed over the second barrier metal layer.