Revealing Wake-Up Mechanism in Ultra-Thin Ferroelectric Hzo: Domain De-Pinning Triggered by Oxygen Vacancy Annihilation Exhibiting Optimal Wake-Up Frequency

We present a new comprehensive model describing wake-up mechanism in ferroelectric <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{Hf}_{0.5} \text{Zr}_{0.5} \mathrm{O}_{2}$</tex> (HZO), a key challenge in reducing operating voltage with sub- 6 nm films. Strong frequency and temperature dependences suggest that thermally-activated oxygen migration driven by electric-field cycling annihilates vacancies and results in domain de-pinning. It is found that oxygens inside HZO films exhibit dispersive transport rather than conventional drift-diffusion transport. Our insight reveals that fast wake-up can be achieved at the optimum frequency that matches with the oxygen migration oscillation frequency.