Wake-Up Free Hf0.5Zr0.5O2 FerroelectricCapacitor by Annealing and Insertinga Top Dielectric Layer

In this work, we realize the fabrication of wake-up free Hf0.5Zr0.5O2 (HZO)-based ferroelectric (FE) capacitors with metal/dielectric layer/ferroelectric/metal (MIFM) structure by annealing and inserting top dielectric layer (DEL). We find that MIFM capacitors with 1-nm Hf0.5Zr0.5O2 , and Al2O3 top DEL still exhibit wake-up free behavior when the annealing temperature decreases from 550 degree celsius. The ab initio calculations reveal that the top DEL suppresses the formation of oxygen vacancies at the TiN/DE and DE/HZO interfaces, which can inhibit the domain pinning effect. In addition, the capacitors with 1-nm DEL demonstrate improved endurance under the same annealing temperature and electric field conditions. Our work is helpful for understanding wake-up effect and for the reliability design of HZO-based FE devices.