Ferroelectric polarization switching dynamics and wake-up effect in Si doped HfO2

Abstract

Ferroelectricity in ultra-thin HfO2 offers a viable alternative for the ferroelectric random access memory. The reliable switching behavior is highly required before commercial applications, whereas many intriguing features have not been understood yet clearly. Herein, we report an increase in the remnant polarization after electric field cycling, known as the wake-up effect, in terms of the change in the polarization switching dynamics of a Si-doped HfO2 thin film. Compared with the pristine specimen, the Si-doped HfO2 thin film exhibited a partial increase in the polarization value after a finite number of ferroelectric switching behaviors. Polarization switching behaviors were analyzed using the nucleation limited switching model, accompanied by defects charged randomly. The polarization switching was simulated using the Monte Carlo method with respect to the effect of defects. Comparing the experimental results with the simulations revealed that the wake-up effect of the HfO2 thin film was due to suppression of chemical disorder.