A novel non-volatile flip-flop using a ferroelectric capacitor

A novel structure for a non-volatile flip-flop (NVFF) was proposed combining the in-series structure (MFMIM) of a ferroelectric capacitor and a dielectric capacitor followed by a CMOS-inverter. It was demonstrated that the proposed NVFF acted as a flip-flop compatible device. Also, even if the entire power supply was turned off, if it was turned on again within 6000 seconds, the last information was restored. A detailed examination of the time dependence of the leakage current of each component revealed that the retention property of NVFF was chiefly controlled by the characteristics of the dielectric relaxation current of the measured ferroelectric capacitor, taking into account the whole history of applied voltage to the ferroelectric capacitor.