Memory transistors based on two-dimensional (2D) ferroelectric semiconductors are intriguing for next-generation in-memory computing. To date, several 2D ferroelectric materials have been unveiled, among which 2D In2Se3 is the most promising, as all the paraelectric (β), ferroelectric (α) and antiferroelectric (β′) phases are found in 2D quintuple layers. However, the large-scale synthesis of 2D In2Se3 films with the desired phase is still absent, and the stability for each phase remains obscure. Here we show the successful growth of centimetre-scale 2D β-In2Se3 film by chemical vapour deposition including distinct centimetre-scale 2D β′-In2Se3 film by an InSe precursor. We also demonstrate that as-grown 2D β′-In2Se3 films on mica substrates can be delaminated or transferred onto flexible or uneven substrates, yielding α-In2Se3 films through a complete phase transition. Thus, a full spectrum of paraelectric, ferroelectric and antiferroelectric 2D films can be readily obtained by means of the correlated polymorphism in 2D In2Se3, enabling 2D memory transistors with high electron mobility, and polarizable β′–α In2Se3 heterophase junctions with improved non-volatile memory performance.
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Si, M. et al. A ferroelectric semiconductor field-effect transistor. Nat. Electron. 2, 580–586 (2019).
Wu, J. B. et al. High tunnelling electroresistance in a ferroelectric van der Waals heterojunction via giant barrier height modulation. Nat. Electron. 3, 466–472 (2020).
Wang, S. et al. Two-dimensional ferroelectric channel transistors integrating ultra-fast memory and neural computing. Nat. Commun. 12, 53 (2021).
Wang, X. W. et al. Van der Waals engineering of ferroelectric heterostructures for long-retention memory. Nat. Commun. 12, 1109 (2021).
Dai, M. et al. Two-dimensional van der Waals materials with aligned in-plane polarization and large piezoelectric effect for self-powered piezoelectric sensors. Nano Lett. 19, 5410–5416 (2019).
Marega, G. M. et al. Logic-in-memory based on an atomically thin semiconductor. Nature 587, 72–77 (2020).
Ielmini, D. & Wong, H.-S. P. In-memory computing with resistive switching devices. Nat. Electron. 1, 333–343 (2018).
Khan, A. I. et al. The future of ferroelectric field-effect transistor technology. Nat. Electron. 3, 588–597 (2020).
Tong, L. et al. 2D materials–based homogeneous transistor-memory architecture for neuromorphic hardware. Science 373, 1353–1358 (2021).
Ding, W. J. et al. Prediction of intrinsic two-dimensional ferroelectrics in In2Se3 and other III2-VI3 van der Waals materials. Nat. Commun. 8, 14956 (2017).
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. et al. Intercorrelated in-plane and out-of-plane ferroelectricity in ultrathin two-dimensional layered semiconductor In2Se3. Nano Lett. 18, 1253–1258 (2018).
Chang, K. et al. Discovery of robust in-plane ferroelectricity in atomic-thick SnTe. Science 353, 274–278 (2016).
Liu, F. et al. Room-temperature ferroelectricity in CuInP2S6 ultrathin flakes. Nat. Commun. 7, 12357 (2016).
Yuan, S. et al. Room-temperature ferroelectricity in MoTe2 down to the atomic monolayer limit. Nat. Commun. 10, 1775 (2019).
Bao, Y. et al. Gate-tunable in-plane ferroelectricity in few-layer SnS. Nano Lett. 19, 5109–5117 (2019).
Zheng, C. et al. Room temperature in-plane ferroelectricity in van der Waals In2Se3. Sci. Adv. 4, eaar7720 (2018).
Xu, C. et al. Two-dimensional antiferroelectricity in nanostripe-ordered In2Se3. Phys. Rev. Lett. 125, 047601 (2020).
Chen, Z. et al. Atomic imaging of electrically switchable striped domains in β′-In2Se3. Adv. Sci. 8, 2100713 (2021).
Zhang, Z. M. et al. Atomic visualization and switching of ferroelectric order in β-In2Se3 films at the single layer limit. Adv. Mater. 33, 202106951 (2021).
Xu, C. et al. Two-dimensional ferroelasticity in van der Waals β’-In2Se3. Nat. Commun. 12, 3665 (2021).
Collins, J. L. et al. Electronic band structure of in-plane ferroelectric van der Waals β′-In2Se3. ACS Appl. Electron. Mater 2, 213–219 (2020).
Han, G. et al. Indium selenides: structural characteristics, synthesis and their thermoelectric performances. Small 10, 2747–2765 (2014).
Tao, X. & Gu, Y. Crystalline−crystalline phase transformation in two-dimensional In2Se3 thin layers. Nano Lett. 13, 3501–3505 (2013).
Liu, L. et al. Atomically resolving polymorphs and crystal structures of In2Se3. Chem. Mater. 31, 10143 (2019).
Balakrishnan, N. et al. Quantum confinement and photoresponsivity of β-In2Se3 nanosheets grown by physical vapour transport. 2D Mater. 3, 025030 (2016).
Rashid, R. et al. Shape-control growth of 2D-In2Se3 with out-of-plane ferroelectricity by chemical vapor deposition. Nanoscale 12, 20189–20201 (2020).
Van Landuyt, J. et al. Phase transitions in In2Se3 as studied by electron microscopy and electron diffraction. Phys. Stat. Sol. (a) 3, 299–314 (1975).
Lin, M. et al. Controlled growth of atomically thin In2Se3 flakes by van der Waals epitaxy. J. Am. Chem. Soc. 135, 13274–13277 (2013).
Balakrishnan, N. et al. Epitaxial growth of-InSe and α, β, and γ-In2Se3 on ε-GaSe. 2D Mater. 5, 035026 (2018).
Li, T. et al. Epitaxial growth of wafer-scale molybdenum disulfide semiconductor single crystals on sapphire. Nat. Nanotechnol. 16, 1201–1207 (2021).
Tang, L. et al. Vertical chemical vapor deposition growth of highly uniform 2D transition metal dichalcogenides. ACS Nano 4, 4646–4653 (2020).
Lakin, N. M. et al. The identification of In2O in the gas phase by high resolution electronic spectroscopy. J. Chem. Phys. 107, 4439–4442 (1997).
Ly, T. H. et al. Edge delamination of monolayer transition metal dichalcogenides. ACS Nano 11, 7534–7541 (2017).
Huang, L. et al. Mechanical origin of martensite-like structures in two-dimensional ReS2. Commun. Mater. 2, 87 (2021).
Vilaplana, R. et al. Experimental and theoretical studies on α‑In2Se3 at high pressure. Inorg. Chem. 57, 8241–8252 (2018).
Li, W., Qian, X. & Li, J. Phase transitions in 2D materials. Nat. Rev. Mater. 6, 829–846 (2021).
Yang, S. X. et al. Strain engineering of two-dimensional materials: methods, properties, and applications. InfoMat 3, 397–420 (2021).
Zhang, X. et al. Epitaxial growth of few-layer β-In2Se3 thin films by metalorganic chemical vapor deposition. J. Cryst. Growth 533, 125471 (2020).
Kang, K. et al. High-mobility three-atom-thick semiconducting films with wafer-scale homogeneity. Nature 520, 656–660 (2015).
Xu, X. L. et al. Seeded 2D epitaxy of large-area single-crystal films of the van der Waals semiconductor 2H MoTe2. Science 372, 195–200 (2021).
Zhou, J. et al. Controlled synthesis of high-quality monolayered α-In2Se3 via physical vapor deposition. Nano Lett. 15, 6400–6405 (2015).
Zheng, Z. Q. et al. Self-assembly of the lateral In2Se3/CuInSe2 heterojunction for enhanced photodetection. ACS Appl. Mater. Interfaces 9, 7288–7296 (2017).
Yuan, S. G. et al. Enhanced piezoelectric response of layered In2Se3/MoS2 nanosheet-based van der Waals heterostructures. ACS Appl. Nano Mater. 3, 11979–11986 (2020).
Igo, J. et al. Photodefined in-plane heterostructures in two-dimensional In2Se3 nanolayers for ultrathin photodiodes. ACS Appl. Nano Mater. 2, 6774–6782 (2019).
Barthel, J. Dr. Probe: a software for high-resolution STEM image simulation. Ultramicroscopy 193, 1–11 (2018).
Blöchl, P. E. Projector augmented-wave method. Phys. Rev. B 50, 17953–17979 (1994).
Kresse, G. & Furthmüller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169 (1996).
Kresse, G. & Furthmüller, J. Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set. Comput. Mater. Sci. 6, 15–50 (1996).
Dion, M. et al. Van der Waals density functional for general geometries. Phys. Rev. Lett. 92, 246401 (2004).
Román-Pérez, G. & Soler, J. M. Efficient implementation of a van der Waals density functional: application to double-wall carbon nanotubes. Phys. Rev. Lett. 103, 096102 (2009).
Klimeš, J., Bowler, D. R. & Michaelides, A. Van der Waals density functionals applied to solids. Phys. Rev. B 83, 195131 (2011).
This work was supported by the National Natural Science Foundation of China (grant nos. 51872248, 51922113, 52173230, 52222218 and 22105162); Hong Kong Research Grant Council Collaborative Research Fund (project no. C5029-18E); the Hong Kong Research Grant Council General Research Fund (project nos. 11300820, 11312022 and 15302419); the City University of Hong Kong (project nos. 9680241 and 9229074); the Hong Kong Polytechnic University (project nos. 1-ZVGH, ZVRP, W147, 1-BE47, ZE0C and ZE2F); and the Shenzhen Science, Technology and Innovation Commission (project no. JCYJ20200109110213442).
The authors declare no competing interests.
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Han, W., Zheng, X., Yang, K. et al. Phase-controllable large-area two-dimensional In2Se3 and ferroelectric heterophase junction. Nat. Nanotechnol. 18, 55–63 (2023). https://doi.org/10.1038/s41565-022-01257-3
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