HfO2-ZrO2 Superlattice Ferroelectric Capacitor With Improved Endurance Performance and Higher Fatigue Recovery Capability

HfO 2 -ZrO 2 superlattice (SL) ferroelectric (FE) capacitor is demonstrated to have improved endurance performance and higher fatigue recovery capability compared to the HfZrO x (HZO) device. During the cycling of polarization ( {P} ) vs. voltage ( {V} ) loops, the SL metal-FE-metal (MFM) capacitor exhibits the higher {P} and the lower leakage current over the HZO device indicating the lower defect density in SL. The SL capacitor achieves an endurance of {5}\times {10} ^{{12}} cycles, which is three orders of magnitude higher than the HZO device. The {P} fatigue of the SL capacitor can be fully recovered through a ~30 s break, and that of HZO is only partially recovered utilizing the higher field cycling. This is because the trapping/detrapping process significantly decreases in HfO 2 -ZrO 2 SL over HZO capacitor by the reduced defect density. These results prove that the HfO 2 -ZrO 2 SL is a promising technology for endurance unlimited FE random access memory.