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Steep-slope hysteresis-free negative capacitance MoS2 transistors

Abstract

The so-called Boltzmann tyranny defines the fundamental thermionic limit of the subthreshold slope of a metal–oxide–semiconductor field-effect transistor (MOSFET) at 60 mV dec−1 at room temperature and therefore precludes lowering of the supply voltage and overall power consumption1,2. Adding a ferroelectric negative capacitor to the gate stack of a MOSFET may offer a promising solution to bypassing this fundamental barrier3. Meanwhile, two-dimensional semiconductors such as atomically thin transition-metal dichalcogenides, due to their low dielectric constant and ease of integration into a junctionless transistor topology, offer enhanced electrostatic control of the channel4,5,6,7,8,9,10,11,12. Here, we combine these two advantages and demonstrate a molybdenum disulfide (MoS2) two-dimensional steep-slope transistor with a ferroelectric hafnium zirconium oxide layer in the gate dielectric stack. This device exhibits excellent performance in both on and off states, with a maximum drain current of 510 μA μm−1 and a sub-thermionic subthreshold slope, and is essentially hysteresis-free. Negative differential resistance was observed at room temperature in the MoS2 negative-capacitance FETs as the result of negative capacitance due to the negative drain-induced barrier lowering. A high on-current-induced self-heating effect was also observed and studied.

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Fig. 1: Schematic and fabrication of MoS2 NC-FETs.
Fig. 2: Off-state switching characteristics of MoS2 NC-FETs.
Fig. 3: NDR and negative DIBL in MoS2 NC-FETs.
Fig. 4: On-state characteristics and self-heating of MoS2 NC-FETs.

References

  1. 1.

    Ionescu, A. M. & Riel, H. Tunnel field-effect transistors as energy-efficient electronic switches. Nature 479, 329–337 (2011).

    Article  Google Scholar 

  2. 2.

    Sze, S. M. & Ng, K. Physics of Semiconductor Devices 3rd edn (Wiley, Hoboken, New Jersey, 2008).

  3. 3.

    Salahuddin, S. & Datta, S. Use of negative capacitance to provide voltage amplification for low power nanoscale devices. Nano Lett. 8, 405–410 (2008).

    Article  Google Scholar 

  4. 4.

    Radisavljevic, B., Radenovic, A., Brivio, J., Giacometti, V. & Kis, A. Single-layer MoS2 transistors. Nature Nanotech. 6, 147–150 (2011).

    Article  Google Scholar 

  5. 5.

    Liu, H., Neal, A. T. & Ye, P. D. Channel length scaling of MoS2 MOSFETs. ACS Nano 6, 8563–8569 (2012).

    Article  Google Scholar 

  6. 6.

    Das, S., Chen, H.-Y., Penumatcha, A. V. & Appenzeller, J. High performance multilayer MoS2 transistors with scandium contacts. Nano Lett. 13, 100–105 (2013).

    Article  Google Scholar 

  7. 7.

    Wang, H. et al. Integrated circuits based on bilayer MoS2 transistors. Nano Lett. 12, 4674–4680 (2012).

    Article  Google Scholar 

  8. 8.

    Desai, S. B. et al. MoS2 transistors with 1-nanometer gate lengths. Science 354, 99–102 (2016).

    Article  Google Scholar 

  9. 9.

    English, C. D., Shine, G., Dorgan, V. E., Saraswat, K. C. & Pop, E. Improved contacts to MoS2 transistors by ultra-high vacuum metal deposition. Nano Lett. 16, 3824–3830 (2016).

    Article  Google Scholar 

  10. 10.

    Liu, Y. et al. Pushing the performance limit of sub-100 nm molybdenum disulfide transistors. Nano Lett. 16, 6337–6342 (2016).

    Article  Google Scholar 

  11. 11.

    Yang, L. et al. Chloride molecular doping technique on 2D materials: WS2 and MoS2. Nano Lett. 14, 6275–6280 (2014).

    Article  Google Scholar 

  12. 12.

    Liu, L., Lu, Y. & Guo, J. On monolayer MoS2 field-effect transistors at the scaling limit. IEEE Trans. Electron. Dev. 60, 4133–4139 (2013).

    Article  Google Scholar 

  13. 13.

    Gopalakrishnan, K., Griffin, P. B. & Plummer, J. D. I-MOS: a novel semiconductor device with a subthreshold slope lower than kT/q. Proc. IEEE Int. Electron. Dev. Meet. 289–292 (2002).

  14. 14.

    Appenzeller, J., Lin, Y.-M., Knoch, J. & Avouris, P. Band-to-band tunneling in carbon nanotube field-effect transistors. Phys. Rev. Lett. 93, 196805 (2004).

    Article  Google Scholar 

  15. 15.

    Sarkar, D. et al. A subthermionic tunnel field-effect transistor with an atomically thin channel. Nature 526, 91–95 (2015).

    Article  Google Scholar 

  16. 16.

    Abele, N. et al. Suspended-gate MOSFET: bringing new MEMS functionality into solid-state MOS transistor. Proc. IEEE Int. Electron. Dev. Meet. 479–481 (2005).

  17. 17.

    Dubourdieu, C. et al. Switching of ferroelectric polarization in epitaxial BaTiO3 films on silicon without a conducting bottom electrode. Nature Nanotech. 8, 748–754 (2013).

    Article  Google Scholar 

  18. 18.

    Jain, A. & Alam, M. A. Stability constraints define the minimum subthreshold swing of a negative capacitance field-effect transistor. IEEE Trans. Electron. Dev. 61, 2235–2242 (2014).

    Article  Google Scholar 

  19. 19.

    Khan, A. I. et al. Negative capacitance in a ferroelectric capacitor. Nat. Mater. 14, 182–186 (2015).

    Article  Google Scholar 

  20. 20.

    Zubko, P. et al. Negative capacitance in multidomain ferroelectric superlattices. Nature 534, 524–528 (2016).

    Article  Google Scholar 

  21. 21.

    McGuire, F. A., Cheng, Z., Price, K. & Franklin, A. D. Sub-60 mV/decade switching in 2D negative capacitance field-effect transistors with integrated ferroelectric polymer. Appl. Phys. Lett. 109, 093101 (2016).

    Article  Google Scholar 

  22. 22.

    Wang, X. et al. Ultrasensitive and broadband MoS2 photodetector driven by ferroelectrics. Adv. Mater. 27, 6575–6581 (2015).

    Article  Google Scholar 

  23. 23.

    Salvatore, G. A., Bouvet, D. & Ionescu, A. M. Demonstration of subthreshold swing smaller than 60 mV/decade in Fe-FET with P(VDF-TrFE)/SiO2 gate stack. Proc. IEEE Int. Electron. Dev. Meet. 167–170 (2008).

  24. 24.

    Muller, J. et al. Ferroelectricity in simple binary ZrO2 and HfO2. Nano Lett. 12, 4318–4323 (2012).

    Article  Google Scholar 

  25. 25.

    Cheng, C. H. & Chin, A. Low-voltage steep turn-on pMOSFET using ferroelectric high-κ gate dielectric. IEEE Electron. Dev. Lett. 35, 274–276 (2014).

    Article  Google Scholar 

  26. 26.

    Lee, M. H. et al. Prospects for ferroelectric HfZrO x FETs with experimentally CET = 0.98 nm, SSfor = 42 mV/dec, SSrev = 28 mV/dec, switch-off <0.2V, and hysteresis-free strategies. Proc. IEEE Int. Electron. Dev. Meet. 616–619 (2015).

  27. 27.

    Zhou, J. et al. Ferroelectric HfZrO x Ge and GeSn PMOSFETs with sub-60 mV/decade subthreshold swing, negligible hysteresis, and improved IDS. Proc. IEEE Int. Electron. Dev. Meet. 310–313 (2016).

  28. 28.

    Li, K. S. et al. Sub-60mV-swing negative-capacitance FinFET without hysteresis. Proc. IEEE Int. Electron. Dev. Meet. 620–623 (2015).

  29. 29.

    Ota, H. et al. Fully coupled 3-D device simulation of negative capacitance FinFETs for sub 10 nm integration. Proc. IEEE Int. Electron. Dev. Meet. 318–321 (2016).

  30. 30

    McGuire, F. A. et al. Sustained sub-60 mV/decade switching via the negative capacitance effect in MoS transistors. Nano Lett. 17, 4801–4806 (2017).

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Acknowledgements

This material is based upon work partly supported by the Air Force Office of Scientific Research (AFOSR)/National Science Foundation (NSF) Two-Dimensional Atomic-layer Research and Engineering (2DARE) programme, Army Research Office (ARO) and Semiconductor Research Corporation (SRC).

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Contributions

P.D.Y. conceived the idea and supervised the experiments. C.J.S. performed the ALD of HZO and Al2O3 and dielectric physical analysis. M.S. performed the device fabrication, d.c. and C–V measurements, and data analysis. M.S. and N.J.C. carried out the fast IV measurement. M.S. and G.Q. performed the AFM measurement. H.Z., K.D.M. and A.S. did the thermo-reflectance imaging. G.Q. performed the Raman and photoluminescence experiment. C.T.W. conducted TEM and EDS analyses. C.J. and A.M.A. conducted the theoretical calculations and analysis. M.S., A.M.A. and P.D.Y. summarized the manuscript and all authors commented on it.

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Correspondence to Peide D. Ye.

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Supplementary Information

Steep Slope Hysteresis-free Negative Capacitance MoS2 Transistors.

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Si, M., Su, CJ., Jiang, C. et al. Steep-slope hysteresis-free negative capacitance MoS2 transistors. Nature Nanotech 13, 24–28 (2018). https://doi.org/10.1038/s41565-017-0010-1

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