Symmetry Engineering in Antiferroelectric ZrO2 Thin Films via Split-Up Behavior

Abstract

Antiferroelectric (AFE) fluorite, e.g., ZrO₂ thin films, is emerging as a promising architecture for energy storage and low-power memory applications due to its mature compatibility with complementary metal-oxide-semiconductor technology. However, despite the considerable potential of AFE materials for memory applications, the manipulation of the double hysteresis of AFE materials remains insufficient. Therefore, we deterministically controlled the split-up behavior of the polarization switching current of 10 nm thick AFE ZrO₂ thin films. Polycrystalline ZrO₂ thin films were deposited on TiN/Si substrates by atomic layer deposition. Then, using conventional current–electric field measurements, we demonstrated that the splitting of the AFE switching current can be controlled by adjusting the applied bias voltage during subloop cycling. First-order reversal curves showed that this split phenomenon represents the separation of the internal bias field. Additionally, we report that the sequential unipolar subloop cycling of different electric fields induced multiple and asymmetric split-up behavior. These findings suggest the possibility of symmetry engineering of the switching current peak in AFE ZrO₂ through conventional electric bias stimulus.