Ferroelectric tunnel junctions use a thin ferroelectric layer as a tunnelling barrier, the height of which can be modified by switching its ferroelectric polarization. The junctions can offer low power consumption, non-volatile switching and non-destructive readout, and thus are promising for the development of memory and computing applications. However, achieving a high tunnelling electroresistance (TER) in these devices remains challenging. Typical junctions, such as those based on barium titanate or hafnium dioxide, are limited by their small barrier height modulation of around 0.1 eV. Here, we report a ferroelectric tunnel junction that uses layered copper indium thiophosphate (CuInP2S6) as the ferroelectric barrier, and graphene and chromium as asymmetric contacts. The ferroelectric field effect in CuInP2S6 can induce a barrier height modulation of 1 eV in the junction, which results in a TER of above 107. This modulation, which is shown using Kelvin probe force microscopy and Raman spectroscopy, is due to the low density of states and small quantum capacitance near the Dirac point of the semi-metallic graphene.
Subscribe to Journal
Get full journal access for 1 year
only $8.25 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Tax calculation will be finalised during checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request.
Garcia, V. & Bibes, M. Ferroelectric tunnel junctions for information storage and processing. Nat. Commun. 5, 4289 (2014).
Garcia, V. et al. Giant tunnel electroresistance for non-destructive readout of ferroelectric states. Nature 460, 81–84 (2009).
Pantel, D., Goetze, S., Hesse, D. & Alexe, M. Reversible electrical switching of spin polarization in multiferroic tunnel junctions. Nat. Mater. 11, 289–293 (2012).
Chanthbouala, A. et al. Solid-state memories based on ferroelectric tunnel junctions. Nat. Nanotechnol. 7, 101–104 (2012).
Garcia, V. et al. Ferroelectric control of spin polarization. Science 327, 1106–1110 (2010).
Zhuravlev, M. Y., Sabirianov, R. F., Jaswal, S. & Tsymbal, E. Y. Giant electroresistance in ferroelectric tunnel junctions. Phys. Rev. Lett. 94, 246802 (2005).
Pantel, D. & Alexe, M. Electroresistance effects in ferroelectric tunnel barriers. Phys. Rev. B 82, 134105 (2010).
Gruverman, A. et al. Tunneling electroresistance effect in ferroelectric tunnel junctions at the nanoscale. Nano Lett. 9, 3539–3543 (2009).
Hambe, M. et al. Crossing an interface: ferroelectric control of tunnel currents in magnetic complex oxide heterostructures. Adv. Funct. Mater. 20, 2436–2441 (2010).
Hoffmann, M. et al. Stabilizing the ferroelectric phase in doped hafnium oxide. J. Appl. Phys. 118, 072006 (2015).
Ambriz-Vargas, F. et al. A complementary metal oxide semiconductor process-compatible ferroelectric tunnel junction. ACS Appl. Mater. Interfaces 9, 13262–13268 (2017).
Xi, Z. et al. Giant tunnelling electroresistance in metal/ferroelectric/semiconductor tunnel junctions by engineering the Schottky barrier. Nat. Commun. 8, 15217 (2017).
Dong, Z., Cao, X., Wu, T. & Guo, J. Tunneling current in HfO2 and Hf0.5Zr0.5O2-based ferroelectric tunnel junction. J. Appl. Phys. 123, 094501 (2018).
Bang, T. et al. Low-frequency noise characteristics in SONOS flash memory with vertically stacked nanowire FETs. IEEE Electron Dev. Lett. 38, 40–43 (2016).
Muller, J. et al. Ferroelectricity in simple binary ZrO2 and HfO2. Nano Lett. 12, 4318–4323 (2012).
Mueller, S. et al. Incipient ferroelectricity in Al‐doped HfO2 thin films. Adv. Funct. Mater. 22, 2412–2417 (2012).
Wen, Z., Li, C., Wu, D., Li, A. & Ming, N. Ferroelectric-field-effect-enhanced electroresistance in metal/ferroelectric/semiconductor tunnel junctions. Nat. Mater. 12, 617–621 (2013).
Liu, F. et al. Room-temperature ferroelectricity in CuInP2S6 ultrathin flakes. Nat. Commun. 7, 12357 (2016).
Ding, W. et al. Prediction of intrinsic two-dimensional ferroelectrics in In2Se3 and other III2-VI3 van der Waals materials. Nat. Commun. 8, 14956 (2017).
Fei, R., Kang, W. & Yang, L. Ferroelectricity and phase transitions in monolayer group-IV monochalcogenides. Phys. Rev. Lett. 117, 097601 (2016).
Chandrasekaran, A., Mishra, A. & Singh, A. K. Ferroelectricity, antiferroelectricity, and ultrathin 2D electron/hole gas in multifunctional monolayer MXene. Nano Lett. 17, 3290–3296 (2017).
Belianinov, A. et al. CuInP2S6 room temperature layered ferroelectric. Nano Lett. 15, 3808–3814 (2015).
You, L. et al. Origin of giant negative piezoelectricity in a layered van der Waals ferroelectric. Sci. Adv. 5, eaav3780 (2019).
Zhou, Y. et al. Out-of-plane piezoelectricity and ferroelectricity in layered α-In2Se3 nanoflakes. Nano Lett. 17, 5508–5513 (2017).
Xue, F. et al. Room‐temperature ferroelectricity in hexagonally layered α‐In2Se3 nanoflakes down to the monolayer limit. Adv. Funct. Mater. 28, 1803738 (2018).
Cui, C., Xue, F., Hu, W.-J. & Li, L.-J. Two-dimensional materials with piezoelectric and ferroelectric functionalities. npj 2D Mater. Appl. 2, 18 (2018).
Si, M., Liao, P.-Y., Qiu, G., Duan, Y. & Ye, P. D. Ferroelectric field-effect transistors based on MoS2 and CuInP2S6 two-dimensional van der Waals heterostructure. ACS Nano 12, 6700–6705 (2018).
Wan, S. et al. Nonvolatile ferroelectric memory effect in ultrathin α‐In2Se3. Adv. Funct. Mater. 29, 1808606 (2019).
Wan, S. et al. Room-temperature ferroelectricity and a switchable diode effect in two-dimensional α-In2Se3 thin layers. Nanoscale 10, 14885–14892 (2018).
Xue, F. et al. Gate-tunable and multidirection-switchable memristive phenomena in a van der Waals ferroelectric. Adv. Mater. 31, e1901300 (2019).
Wang, X. et al. Van der Waals negative capacitance transistors. Nat. Commun. 10, 3037 (2019).
Kang, K. et al. High-mobility three-atom-thick semiconducting films with wafer-scale homogeneity. Nature 520, 656–660 (2015).
Lin, Y.-M. et al. Wafer-scale graphene integrated circuit. Science 332, 1294–1297 (2011).
Wang, L. et al. Epitaxial growth of a 100-square-centimetre single-crystal hexagonal boron nitride monolayer on copper. Nature 570, 91–95 (2019).
Maisonneuve, V., Evain, M., Payen, C., Cajipe, V. & Molinie, P. Room-temperature crystal structure of the layered phase CuIInIIIP2S6. J. Alloys Compd. 218, 157–164 (1995).
Susner, M. A. et al. High-Tc layered ferrielectric crystals by coherent spinodal decomposition. ACS Nano 9, 12365–12373 (2015).
Qiao, J., Kong, X., Hu, Z.-X., Yang, F. & Ji, W. High-mobility transport anisotropy and linear dichroism in few-layer black phosphorus. Nat. Commun. 5, 4475 (2014).
Sangwan, V. K. & Hersam, M. C. Electronic transport in two-dimensional materials. Annu. Rev. Phys. Chem. 69, 299–325 (2018).
Wu, J.-B., Lin, M.-L., Cong, X., Liu, H.-N. & Tan, P.-H. Raman spectroscopy of graphene-based materials and its applications in related devices. Chem. Soc. Rev. 47, 1822–1873 (2018).
Chen, C.-F. et al. Controlling inelastic light scattering quantum pathways in graphene. Nature 471, 617–620 (2011).
Das, A. et al. Monitoring dopants by Raman scattering in an electrochemically top-gated graphene transistor. Nat. Nanotechnol. 3, 210–215 (2008).
Zhao, W., Tan, P. H., Liu, J. & Ferrari, A. C. Intercalation of few-layer graphite flakes with FeCl3: Raman determination of Fermi level, layer by layer decoupling and stability. J. Am. Chem. Soc. 133, 5941–5946 (2011).
Li, H. et al. Interfacial interactions in van der Waals heterostructures of MoS2 and graphene. ACS Nano 11, 11714–11723 (2017).
Sun, Y. et al. Band structure engineering of interfacial semiconductors based on atomically thin lead iodide crystals. Adv. Mater. 31, 1806562 (2019).
Baeumer, C., Rogers, S. P., Xu, R., Martin, L. W. & Shim, M. Tunable carrier type and density in graphene/PbZr0.2Ti0.8O3 hybrid structures through ferroelectric switching. Nano Lett. 13, 1693–1698 (2013).
Baeumer, C. et al. Ferroelectrically driven spatial carrier density modulation in graphene. Nat. Commun. 6, 6136 (2015).
Hu, W. J., Wang, Z., Yu, W. & Wu, T. Optically controlled electroresistance and electrically controlled photovoltage in ferroelectric tunnel junctions. Nat. Commun. 7, 10808 (2016).
Jiang, J. et al. Flexible ferroelectric element based on van der Waals heteroepitaxy. Sci. Adv. 3, e1700121 (2017).
J.W., H.-Y.C. and H.W. acknowledge support from the Army Research Office Young Investigator Program (grant W911NF-18-1-0268) and the National Science Foundation (grant CCF-1618038). N.Y. and J.G. acknowledge support from the National Science Foundation (grants 1618762, 1610387 and 1904580). J.C. and X.L. acknowledge support from the Semiconductor Research Corporation (SRC).
The authors declare no competing interests.
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
About this article
Cite this article
Wu, J., Chen, HY., Yang, N. et al. High tunnelling electroresistance in a ferroelectric van der Waals heterojunction via giant barrier height modulation. Nat Electron 3, 466–472 (2020). https://doi.org/10.1038/s41928-020-0441-9
Advanced Materials (2021)
Nano Research (2021)
Nature Reviews Materials (2021)
Science Advances (2021)
Nonvolatile Electric Control of Exciton Complexes in Monolayer MoSe2 with Two-Dimensional Ferroelectric CuInP2S6
ACS Applied Materials & Interfaces (2021)