Field‐Effect Transistors from Artificial Charged Domain Walls in Stacked Van der Waals Ferroelectric α‐In ₂ Se ₃

Abstract

ABSTRACT Ferroelectric charged domain walls (CDWs) offer emergent electronic states that can serve as functional elements in high‐density nonvolatile memory and neuromorphic computing. Yet, poor conductivity, structural instability, and lack of deterministic control limit their practical use. Moreover, the CDWs are typically out‐of‐plane and buried interfaces, which prohibits electrical access and prevents gate control of their carrier density. This work demonstrates the fabrication of artificial in‐plane CDWs by stacking oppositely polarized flakes of van der Waals (vdW) ferroelectric ‐In 2 Se 3 . Edge contact is utilized to electrically access the CDWs and integrate them into CDW‐based field‐effect transistors (CDW‐FETs). CDW‐FETs exhibit room‐temperature conductance up to four orders of magnitude higher than single domains, exceeding previously reported CDWs by 2–9 orders of magnitude. Electron microscopy imaging reveals atomic reconstruction and interfacial heterogeneity in CDWs. Temperature and gate‐dependent electrical and magneto‐transport measurements confirm that interfacial band bending governs transport. Two transport mechanisms are identified in these CDW‐FETs: variable‐range hopping and thermally activated traps, showing a transition temperature of 80 K. These results establish artificial CDWs as on‐demand, designable conductive channels in vdW ferroelectrics, advancing the understanding of CDW conduction mechanisms and bridging the gap toward device integration.