Effect of wake-up on the polarization switching dynamics of Si doped HfO2 thin films with imprint

Abstract

We investigated the effect of wake-up on the polarization switching dynamics of Si doped HfO2 thin films with an imprint. From the polarization-voltage hysteresis loops, wake-up and imprint effects were observed. We measured the polarization switched by the voltage pulse at various durations and voltages. The switching behaviors could be explained by the nucleation-limited-switching model with a Lorentzian distribution of the characteristic switching time. Due to the wake-up phenomena, the center of the distribution increased, and the width became narrower, which could be related to improvement of the uniformity of the film. The polarization switching data from the positive and negative bias pulses was analyzed by using the same empirical equation with the effective electric-field corrected for the imprint effect. The increase of the characteristic time due to wake-up was carried out by an increase in the field-independent coefficient, tau(1), without a change in the activation field, alpha. (C) 2020 Elsevier B.V. All rights reserved.