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Abstract Utilizing the unique in‐plane/out‐of‐plane polarization coupling in ferroelectric van der Waals α‐In2Se3, ferroelectric‐polarization‐controlled electrical conductance modulation in two‐dimensional (2D) MoS2with a large dynamic range of over 5 orders of magnitude and excellent non‐volatility is demonstrated. This highly efficient control of the electrical conductance is facilitated by enhanced capacitive coupling through atomic‐layer‐deposition‐grown Al2O3as the dielectric medium. By varying the in‐plane poling bias to the ferroelectric α‐In2Se3, the electrical conductance of vertically stacked 2D MoS2can be tuned continuously. This approach enables simplified device design and provides great flexibility in device integrations, and it can be applied in principle to manipulate the electronic states in any 2D semiconductors for various applications such as transistors, tunneling devices, and reconfigurable electronics. The results also provide insight into the ferroelectric polarization screening by ambient chemical species, highlighting the need for surface passivation, and/or device encapsulations.
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This content will become publicly available on April 1, 2027
Field‐Effect Transistors from Artificial Charged Domain Walls in Stacked Van der Waals Ferroelectric α‐In 2 Se 3
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 ‐In2Se3. 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.
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- Award ID(s):
- 2309037
- PAR ID:
- 10683439
- Publisher / Repository:
- Advanced Materials
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 38
- Issue:
- 20
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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