Improving the endurance for ferroelectric Hf_0.5Zr_0.5O₂ thin films by interface and defect engineering

Improving the endurance performance for hafnia-based ferroelectric thin films and devices is of considerable significance from both scientificand technological perspectives. Here, we obtained robust ferroelectricity in Hf0.5Zr0.5O2(HZO) thin films without the need of the confine-ment from top electrodes by systematically optimizing the conditions and parameters for the post-deposition annealing (PDA) process.Compared with the post-metallization annealing (PMA) process, PDA is found to markedly improve the ferroelectric endurance perfor-mance. In particular, wake-up-free ferroelectric HZO thin films with an exceptional endurance performance (similar to 3X10(10)cycles) are obtainedby PDA processing conducted under an oxygen atmosphere, which is attributed to the suppression of oxygen deficiency in the HZO thinfilms and the inhibition of interfacial reaction layer that inevitably forms during annealing treatment for PMA processing. Our work offersinsight into improving ferroelectricity and endurance for hafnia-based ferroelectric materials and devices.