High-Performance Negative Capacitance Field-Effect Transistors with Synthetic Monolayer MoS<sub>2</sub>
Although negative capacitance field-effect transistors (NCFETs) have been extensively studied to overcome the fundamental Boltzmann limit, many prior reports on sub-60 mV/dec subthreshold swings (SS) suffer from inadequate data ranges, measurements near the noise floor, and a lack of robust device simulations, raising questions about the true efficacy of NCFETs. Moreover, recent efforts with MoS<sub>2</sub> channels have frequently relied on mechanically exfoliated flakes, limiting device uniformity and scalability. Here, we present an NCFET that employs a synthetic monolayer MoS<sub>2</sub> channel and a ferroelectric hafnium zirconium oxide layer in the gate stack integrated with indium metal contacts. We achieve a clearly substantiated subthermionic SS (∼55 mV/dec) across more than two decades of drain current, supported by theoretical modeling that incorporates interface trap density. Additionally, the negative drain-induced barrier lowering (DIBL)-induced threshold voltage shift, a hallmark of NCFETs, is distinctly observed. Compared to existing 2D van der Waals (vdW) NCFETs that rely on exfoliated material, our synthetic monolayer MoS<sub>2</sub> approach demonstrates a reliable and reproducible low-voltage operation, underlining its potential for large-area integration. We further confirm that reducing source/drain contact resistance (achieved with indium metal contacts) is vital for the successful implementation of monolayer 2D vdW NCFETs.
Authors
- Yeonghun Lee (ORCID: https://orcid.org/0000-0002-6058-1316)
- Ji‐Hoon Ahn (ORCID: https://orcid.org/0000-0001-6928-4038)
- Hyeonseo Lee
- Hyo‐Bae Kim
- Ki Kang Kim (ORCID: https://orcid.org/0000-0003-1008-6744)
- Moonyoung Jung (ORCID: https://orcid.org/0000-0002-5467-9085)
- Junhong Na (ORCID: https://orcid.org/0000-0002-5314-2868)
- Dongseok Suh (ORCID: https://orcid.org/0000-0002-0392-3391)
- Seunghyun Oh (ORCID: https://orcid.org/0009-0005-6026-7254)
- Jeong-Min Park (ORCID: https://orcid.org/0000-0003-3534-7947)
- Yungyeong Park
Institutions
- Incheon National University (KR)
- Kangwon National University (KR)
- Ewha Womans University Medical Center (KR)
- Hanyang University (KR)
- Sungkyunkwan University (KR)
Publication Details
- Journal
- ACS Nano
- Published
- 2025-05-02
- DOI
- https://doi.org/10.1021/acsnano.4c18973
- Citations
- 6
- Primary Topic
- Ferroelectric and Negative Capacitance Devices
- Type
- article
- Field-Weighted Citation Impact
- 4.38
Funders
- Ewha Womans University
- Ministry of Trade, Industry and Energy
- National Research Foundation of Korea