Antifuses are known and widely used in programming integrated circuits, including analog and digital circuits, system-on-chips (SOCs), one-time programmable and field programmable gate array (OTP/FPGA), and the like. In general, an antifuse includes a layer of dielectric material, also referred to as an antifuse layer, sandwiched between a pair of electrodes. When un-programmed, an antifuse is non-conductive or in a high resistance state (“off-state”). An antifuse becomes permanently conductive or in a low resistance state (“on-state”) when programmed by applying a voltage in excess of the breakdown voltage of the antifuse layer.
In applications, conventional antifuse structures still show relatively high resistance even in the on-state after programming, resulting in high power consumption of the integrated circuit. Furthermore, in fabrication of conventional antifuse structures, the antifuse layer is defined by photolithography and etching processes, which may cause unpredictable misalignment between the antifuse layer and the electrodes.