Competing Ferroelectric Polarization and Defect Migration Induced Resistive Switching in Van Der Waals β-In₂Se₃

This work systematically investigates the in-plane resistive switching behavior of representative van der Waals (vdW) ferroelectric β’-In<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>Se<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>. Besides resistive switching resulting from ferroelectric polarization reversal, the critical role of Se vacancy migration is unveiled in determining the overall electrical characteristics of β’-In<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>Se<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> devices through time-dependent current evolution, in-situ electric force microscopy (EFM) and density functional theory (DFT) calculations. By considering the interplay between switchable bound charges and mobile defects, a comprehensive physical picture of the complex hysteretic behavior of β’-In<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>Se<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> devices is established.