Abstract
Integrated circuits based on two-dimensional semiconductors require ultrathin gate insulators that can provide high interface quality and dielectric reliability, minimized electrically active traps and efficient gate controllability. However, existing two-dimensional insulators do not provide a good trade-off in terms of bandgap, breakdown strength, dielectric constant, leakage current and bias temperature stability. Here, we show that single crystals of magnesium niobate (MgNb2O6) can be obtained through a buffer-controlled epitaxial growth process on a mica substrate. The atomically thin MgNb2O6 crystals have a wide bandgap (around 5.0 eV), high dielectric constant (around 20), large breakdown voltage (around 16 MV cm−1) and good thermal reliability. The MgNb2O6 can form a van der Waals interface with monolayer molybdenum disulfide (MoS2) with an extremely low density of trap states. MoS2 field-effect transistors with MgNb2O6 gate dielectrics exhibit a hysteresis under 0.9 mV (MV cm−1)−1, a subthreshold swing of 62 mV dec−1, an on/off current ratio of up to 4 × 107 and high electrical reliability at 500 K. The excellent electrostatic controllability of MgNb2O6 allowed us to create graphene-contacted transistors and inverter circuits with a channel length of 50 nm.
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References
Das, S. et al. Transistors based on two-dimensional materials for future integrated circuits. Nat. Electron. 4, 786–799 (2021).
Liu, L. et al. Uniform nucleation and epitaxy of bilayer molybdenum disulfide on sapphire. Nature 605, 69–75 (2022).
Osada, M. & Sasaki, T. Two‐dimensional dielectric nanosheets: novel nanoelectronics from nanocrystal building blocks. Adv. Mater. 24, 210–228 (2012).
Illarionov, Y. Y. et al. Insulators for 2D nanoelectronics: the gap to bridge. Nat. Commun. 11, 3385 (2020).
Li, W. et al. Uniform and ultrathin high-κ gate dielectrics for two-dimensional electronic devices. Nat. Electron. 2, 563–571 (2019).
Zhu, C. Y. et al. 2D indium phosphorus sulfide (In2P3S9): an emerging van der Waals high‐k dielectrics. Small 18, 2104401 (2022).
Luo, P. et al. Molybdenum disulfide transistors with enlarged van der Waals gaps at their dielectric interface via oxygen accumulation. Nat. Electron. 5, 849–858 (2022).
Lu, Z. et al. Wafer-scale high-κ dielectrics for two-dimensional circuits via van der Waals integration. Nat. Commun. 14, 2340 (2023).
Huang, J. K. et al. High-κ perovskite membranes as insulators for two-dimensional transistors. Nature 605, 262–267 (2022).
Li, S. et al. Two-dimensional perovskite oxide as a photoactive high-κ gate dielectric. Nat. Electron. 7, 216–224 (2024).
Zhang, C. et al. Single-crystalline van der Waals layered dielectric with high dielectric constant. Nat. Mater. 22, 832–837 (2023).
Lanza, M. et al. Yield, variability, reliability, and stability of two-dimensional materials based solid-state electronic devices. Nat. Commun. 11, 5689 (2020).
Knobloch, T. et al. Improving stability in two-dimensional transistors with amorphous gate oxides by Fermi-level tuning. Nat. Electron. 5, 356–366 (2022).
Yang, A. J. et al. Van der Waals integration of high-κ perovskite oxides and two-dimensional semiconductors. Nat. Electron. 5, 233–240 (2022).
Pullar, R. C. The synthesis, properties, and applications of columbite niobates (M2+Nb2O6): a critical review. J. Am. Ceram. Soc. 92, 563–577 (2009).
Huang, C. L. et al. Miniaturization of hairpin bandpass filters using high‐permittivity substrate. Microw. Opt. Technol. Lett. 45, 222–225 (2005).
Zaldo, C. et al. Optical properties of MgNb2O6 single crystals: a comparison with LiNbO3. J. Phys. Condens. Matter 7, 2249 (1995).
Shanker, V. & Ganguli, A. K. Comparative study of dielectric properties of MgNb2O6 prepared by molten salt and ceramic method. Bull. Mater. Sci. 26, 741–744 (2003).
Graef, M. (ed.) International Roadmap for Devices and Systems 2022 Update (IEEE, 2022); https://irds.ieee.org/images/files/pdf/2022/2022IRDS_WP-MtM.pdf
Xu, D. et al. Optical phonon behavior of columbite MgNb2O6 single crystals. J. Appl. Phys. 116, 083509 (2014).
Tulyaganov, D. et al. Synthesis and characterization of synthetic F-mica containing glass-ceramics in the system SiO2·Al2O3·B2O3·CaO·MgO·Li2O·(K, Na)2O·F. J. Mater. Res. 19, 1234–1242 (2004).
Mustafa, E. A. Fluorophlogopite porcelain based on talc–feldspar mixture. Ceram. Int. 27, 9–14 (2001).
Li, X. et al. Controlled growth of large-area anisotropic ReS2 atomic layer and its photodetector application. Nanoscale 8, 18956–18962 (2016).
Zhou, S. et al. Space-confined vapor deposition synthesis of two dimensional materials. Nano Res. 11, 2909–2931 (2018).
Huang, F. et al. High pressure Raman scattering and X-ray diffraction studies of MgNb2O6. RSC Adv. 3, 13210–13213 (2013).
Wang, C. et al. Alloy-buffer-controlled van der Waals epitaxial growth of aligned tellurene. Nano Res. 15, 5712–5718 (2022).
Lin, Y. S. et al. Dielectric property and thermal stability of HfO2 on silicon. Appl. Phys. Lett. 81, 2041–2043 (2002).
Cho, B. O. et al. Tuning the electrical properties of zirconium oxide thin films. Appl. Phys. Lett. 80, 1052–1054 (2002).
Robertson, J. High dielectric constant oxides. Eur. Phys. J. Appl. Phys. 28, 265–291 (2004).
Peng, J. et al. Inorganic low κ cage-molecular crystals. Nano Lett. 21, 203–208 (2020).
Yang, K. et al. Ultrathin high-κ antimony oxide single crystals. Nat. Commun. 11, 2502 (2020).
Robertson, J. High dielectric constant gate oxides for metal oxide Si transistors. Rep. Prog. Phys. 69, 327 (2005).
Kim, S. M. et al. Synthesis of large-area multilayer hexagonal boron nitride for high material performance. Nat. Commun. 6, 8662 (2015).
Liu, K. et al. A wafer-scale van der Waals dielectric made from an inorganic molecular crystal film. Nat. Electron. 4, 906–913 (2021).
Momose, H. S. et al. Study of the manufacturing feasibility of 1.5-nm direct-tunneling gate oxide MOSFETs: uniformity, reliability, and dopant penetration of the gate oxide. IEEE Trans. Electron Devices 45, 691–700 (1998).
Park, D. G. et al. Characteristics of n+ polycrystalline-Si/Al2O3/Si metal–oxide–semiconductor structures prepared by atomic layer chemical vapor deposition using Al(CH3)3 and H2O vapor. J. Appl. Phys. 89, 6275–6280 (2001).
Kang, L. et al. Electrical characteristics of highly reliable ultrathin hafnium oxide gate dielectric. IEEE Electron Device Lett. 21, 181–183 (2000).
Manchanda, L. et al. Si-doped aluminates for high temperature metal-gate CMOS: Zr-Al-Si-O, a novel gate dielectric for low power applications. In Proc. International Electron Devices Meeting 2000. Technical Digest (IEDM) 23–26 (IEEE, 2000).
Wen, C. et al. Dielectric properties of ultrathin CaF2 ionic crystals. Adv. Mater. 32, 2002525 (2020).
Sokolov, N. et al. Low-leakage MIS structures with 1.5–6 nm CaF2 insulating layer on Si (111). Microelectron. Eng. 84, 2247–2250 (2007).
Baumert, B. et al. Characterization of sputtered barium strontium titanate and strontium titanate-thin films. J. Appl. Phys. 82, 2558–2566 (1997).
Grasser, T. et al. The paradigm shift in understanding the bias temperature instability: from reaction–diffusion to switching oxide traps. IEEE Trans. Electron Devices 58, 3652–3666 (2011).
Chang, W. H. et al. ALD-ZrO2 gate dielectric with suppressed interfacial oxidation for high performance MoS2 top gate MOSFETs. Jpn J. Appl. Phys. 60, SBBH03 (2021).
Wen, M. et al. Effects of annealing on electrical performance of multilayer MoS2 transistors with atomic layer deposited HfO2 gate dielectric. Appl. Phys. Express 9, 095202 (2016).
Li, T. et al. Electrical performance of multilayer MoS2 transistors on high-κ Al2O3 coated Si substrates. AIP Adv. 5, 057102 (2015).
Uchiyama, H. et al. A monolayer MoS2 FET with an EOT of 1.1 nm achieved by the direct formation of a high-κ Er2O3 insulator through thermal evaporation. Small 19, 2207394 (2023).
Zhou, C. et al. Low voltage and high on/off ratio field-effect transistors based on CVD MoS2 and ultra high-κ gate dielectric PZT. Nanoscale 7, 8695–8700 (2015).
Li, W. et al. High-performance CVD MoS2 transistors with self-aligned top-gate and bi contact. In Proc. 2021 IEEE International Electron Devices Meeting (IEDM) 37.3.1–37.3.4 (IEEE, 2021).
Illarionov, Y. Y. et al. Ultrathin calcium fluoride insulators for two-dimensional field-effect transistors. Nat. Electron. 2, 230–235 (2019).
Zou, X. et al. Interface engineering for high‐performance top‐gated MoS2 field‐effect transistors. Adv. Mater. 26, 6255–6261 (2014).
Xu, F. et al. Few-layered MnAl2S4 dielectrics for high-performance van der Waals stacked transistors. ACS Appl. Mater. Interfaces 14, 25920–25927 (2022).
Chamlagain, B. et al. Thermally oxidized 2D TaS2 as a high-κ gate dielectric for MoS2 field-effect transistors. 2D Mater. 4, 031002 (2017).
Illarionov, Y. Y. et al. Improved hysteresis and reliability of MoS2 transistors with high-quality CVD growth and Al2O3 encapsulation. IEEE Electron Device Lett. 38, 1763–1766 (2017).
Huang, H. et al. Total dose irradiation-induced degradation of hysteresis effect in partially depleted silicon-on-insulator NMOSFETs. IEEE Trans. Nucl. Sci. 60, 1354–1360 (2013).
Yang, Z. et al. Performance limits of the self-aligned nanowire top-gated MoS2 transistors. Adv. Funct. Mater. 27, 1602250 (2017).
Wong, H. & Iwai, H. On the scaling of subnanometer EOT gate dielectrics for ultimate nano CMOS technology. Microelectron. Eng. 138, 57–76 (2015).
Tang, J. et al. Vertical integration of 2D building blocks for all‐2D electronics. Adv. Electron. Mater. 6, 2000550 (2020).
Xie, L. et al. Graphene‐contacted ultrashort channel monolayer MoS2 transistors. Adv. Mater. 29, 1702522 (2017).
Qiu, C. et al. Scaling carbon nanotube complementary transistors to 5-nm gate lengths. Science 355, 271–276 (2017).
English, C. D. et al. Approaching ballistic transport in monolayer MoS2 transistors with self-aligned 10 nm top gates. In Proc. 2016 IEEE International Electron Devices Meeting (IEDM) 5.6.1–5.6.4 (IEEE, 2016).
Auth, C. et al. A 22 nm high performance and low-power CMOS technology featuring fully-depleted tri-gate transistors, self-aligned contacts and high density MIM capacitors. In Proc. 2012 Symposium on VLSI Technology (VLSIT) 131–132 (IEEE, 2012).
Kohn, W. et al. Density functional theory of electronic structure. J. Phys. Chem. 100, 12974–12980 (1996).
Ghoshal, D. et al. Orientation-controlled large-area epitaxial PbI2 thin films with tunable optical properties. ACS Appl. Mater. Interfaces 13, 32450–32460 (2021).
Acknowledgements
This work was supported by the National Key R&D Program of China (Grant Nos 2022YFA1203802 to J.-K.Q. and 2021YFB3601202 to J.W.), the National Natural Science Foundation of China (Grant Nos 52102161 to J.-K.Q. and 62204056 to J.W.), the Shenzhen Science and Technology Program (Grant Nos RCYX20221008092912045 to J.-K.Q., RCJC20210706091950025 to C.-Y.X. and JCYJ20220530115204009 to F.Z.) and Shanghai Science and Technology Development Funds (Grant No. 22YF1402700 to J.W.).
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C.-Y.Z., M.-R.Z. and Q.C. contributed equally to the work. J.-K.Q., J.W., Y.C. and C.-Y.X. conceived the idea and proposed the research. C.-Y.Z., L.-Q.Y. and Y.L. performed the growth experiments and analysed the experimental data. R.S. and J.L. performed and supervised the growth of monolayer MoS2 films. H.-Z.L and W.Z. fabricated the Hall bar devices and performed the electrical measurements. C.-Y.Z., M.-R.Z., F.Z., M.S. and L.Z. fabricated the devices and analysed the experimental data. Q.C., C.W. and Y.C. performed and supervised the DFT calculations. J.-K.Q., C.-Y.Z., J.W., Y.C. and C.-Y.X. co-wrote the manuscript.
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Zhu, CY., Zhang, MR., Chen, Q. et al. Magnesium niobate as a high-κ gate dielectric for two-dimensional electronics. Nat Electron 7, 1137–1146 (2024). https://doi.org/10.1038/s41928-024-01245-6
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DOI: https://doi.org/10.1038/s41928-024-01245-6
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