Competing Ferroelectric Polarization and Defect Migration Induced Resistive Switching in β′-In<sub>2</sub>Se<sub>3</sub>
Yinfeng Long, Saiyu Bu, Han Chen, Kai Liu, Xin Zhou, Shiyu Zhang, Xiaotian Zhang, Teng Zhang, Changxin Chen, Wugang Liao, Kian Ping Loh, Lin Wang
Abstract
Layered β′-In 2 Se 3 has garnered significant attention due to its intriguing multiferroic properties. Until now, most studies have focused on a material-level understanding, with limited exploration of device-level properties. This work systematically investigates the in-plane resistive switching behavior of β′-In 2 Se 3 . Besides resistive switching resulting from ferroelectric polarization reversal, the critical role of defect migration is unveiled in determining the overall electrical characteristics of β′-In 2 Se 3 devices. Specifically, we elucidate the contribution of electric-field-induced Se vacancy migration to resistive switching through time-dependent current evolution, in situ electric force microscopy, and density functional theory calculations. By considering the interplay between free carriers, bound charges, and mobile defects, a comprehensive physical picture of the complex resistive switching behavior of β′-In 2 Se 3 devices is established. This work provides crucial insights into understanding and manipulating the resistive switching behavior of 2D vdW ferroelectric devices.