High‐Performance and Scalable Ferroelectric Diodes Enabled via 2D‐MoS <sub>2</sub> Buffer Layer Under Low Thermal Budget
Hafnium-based (Hf<sub>0.5</sub>Zr<sub>0.5</sub>O<sub>2</sub>, HZO) ferroelectrics exhibit robust polarization switching even in ultrathin films and are compatible with atomic layer deposition (ALD), making them promising for two-terminal (2-T) non-volatile memory devices. However, their practical use remains limited by low ON/OFF ratios, high leakage currents, and poor endurance. Herein, A high-performance ferroelectric diode (FE-diode) based on a W/MoS<sub>2</sub>/HZO/TiN stack is demostrated, fabricated entirely below 400 °C for back-end-of-line (BEOL) compatibility. Two strategies are employed: 1) optimization of the HZO thickness and 2) insertion of a 2D MoS<sub>2</sub> buffer layer at the top electrode/ferroelectric interface. Increasing the HZO thickness from 3 to 8 nm changed the dominant conduction mechanism from direct tunneling to Schottky emission, enabling polarization-driven barrier modulation. The MoS<sub>2</sub> buffer, synthesized via low-temperature (<300 °C) atmospheric pressure plasma-enhanced CVD, minimized interfacial defects and improved device stability. As a result, the FE-diode exhibited a high current density of 50 A cm<sup>-</sup> <sup>2</sup> (read at 3 V), an electroresistance ratio exceeding 2 × 10<sup>6</sup>, endurance over 10<sup>10</sup> cycles, and stable memory retention of 10 years at room temperature. A 1 K (32 × 32) memory array is also demonstrated, confirming excellent scalability and the strong potential of this FE-diode design for next-generation integrated memory applications.
Authors
- Jongwon Yoon (ORCID: https://orcid.org/0000-0001-6425-6046)
- Kim Yonghun
- Laeyong Jung (ORCID: https://orcid.org/0000-0001-6168-4985)
- Hyunsang Hwang (ORCID: https://orcid.org/0000-0003-1930-1914)
- Hojung Jang (ORCID: https://orcid.org/0000-0002-8343-5784)
- Seungkwon Hwang
- Kyumin Lee (ORCID: https://orcid.org/0000-0002-9737-5858)
- Byeongjin Park (ORCID: https://orcid.org/0000-0003-3607-6755)
- Jung‐Dae Kwon (ORCID: https://orcid.org/0000-0002-3535-6360)
- Seock‐Jin Jeong (ORCID: https://orcid.org/0009-0009-5220-2441)
Institutions
- Pohang University of Science and Technology (KR)
- Korea Institute of Materials Science (KR)
Publication Details
- Journal
- Small
- Published
- 2025-10-07
- DOI
- https://doi.org/10.1002/smll.202508853
- Primary Topic
- Ferroelectric and Negative Capacitance Devices
- Type
- article
- Field-Weighted Citation Impact
- 0.00