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High-speed graphene transistors with a self-aligned nanowire gate


Graphene has attracted considerable interest as a potential new electronic material1,2,3,4,5,6,7,8,9,10,11. With its high carrier mobility, graphene is of particular interest for ultrahigh-speed radio-frequency electronics12,13,14,15,16,17,18. However, conventional device fabrication processes cannot readily be applied to produce high-speed graphene transistors because they often introduce significant defects into the monolayer of carbon lattices and severely degrade the device performance19,20,21. Here we report an approach to the fabrication of high-speed graphene transistors with a self-aligned nanowire gate to prevent such degradation. A Co2Si–Al2O3 core–shell nanowire is used as the gate, with the source and drain electrodes defined through a self-alignment process and the channel length defined by the nanowire diameter. The physical assembly of the nanowire gate preserves the high carrier mobility in graphene, and the self-alignment process ensures that the edges of the source, drain and gate electrodes are automatically and precisely positioned so that no overlapping or significant gaps exist between these electrodes, thus minimizing access resistance. It therefore allows for transistor performance not previously possible. Graphene transistors with a channel length as low as 140 nm have been fabricated with the highest scaled on-current (3.32 mA μm−1) and transconductance (1.27 mS μm−1) reported so far. Significantly, on-chip microwave measurements demonstrate that the self-aligned devices have a high intrinsic cut-off (transit) frequency of fT = 100–300 GHz, with the extrinsic fT (in the range of a few gigahertz) largely limited by parasitic pad capacitance. The reported intrinsic fT of the graphene transistors is comparable to that of the very best high-electron-mobility transistors with similar gate lengths10.

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Figure 1: Schematic illustration of a high-speed graphene transistor with a Co 2 Si–Al 2 O 3 core–shell nanowire as the self-aligned top-gate.
Figure 2: Characterization of Co 2 Si and Co 2 Si–Al 2 O 3 core–shell nanowires.
Figure 3: Room-temperature electrical characteristics of the graphene transistors with a self-aligned nanowire gate.
Figure 4: Measured small-signal current gain | h 21 | as a function of frequency f at V ds = −1 V.


  1. Novoselov, K. S. et al. Electric field effect in atomically thin carbon films. Science 306, 666–669 (2004)

    ADS  CAS  Article  Google Scholar 

  2. Novoselov, K. S. et al. Two-dimensional gas of massless Dirac fermions in graphene. Nature 438, 197–200 (2005)

    ADS  CAS  Article  Google Scholar 

  3. Zhang, Y. B., Tan, Y. W., Stormer, H. L. & Kim, P. Experimental observation of the quantum Hall effect and Berry’s phase in graphene. Nature 438, 201–204 (2005)

    ADS  CAS  Article  Google Scholar 

  4. Bunch, J. S., Yaish, Y., Brink, M., Bolotin, K. & McEuen, P. L. Coulomb oscillations and Hall effect in quasi-2D graphite quantum dots. Nano Lett. 5, 287–290 (2005)

    ADS  CAS  Article  Google Scholar 

  5. Berger, C. et al. Electronic confinement and coherence in patterned epitaxial graphene. Science 312, 1191–1196 (2006)

    ADS  CAS  Article  Google Scholar 

  6. Avouris, P., Chen, Z. H. & Perebeinos, V. Carbon-based electronics. Nature Nanotechnol. 2, 605–615 (2007)

    ADS  CAS  Article  Google Scholar 

  7. Miao, F. et al. Phase-coherent transport in graphene quantum billiards. Science 317, 1530–1533 (2007)

    ADS  CAS  Article  Google Scholar 

  8. Bolotin, K. I. et al. Ultrahigh electron mobility in suspended graphene. Solid State Commun. 146, 351–355 (2008)

    ADS  CAS  Article  Google Scholar 

  9. Geim, A. K. & Novoselov, K. S. The rise of graphene. Nature Mater. 6, 183–191 (2007)

    ADS  CAS  Article  Google Scholar 

  10. Schwierz, F. Graphene transistors. Nature Nanotechnol. 5, 487–496 (2010)

    ADS  CAS  Article  Google Scholar 

  11. Meric, I. et al. Current saturation in zero-bandgap, top-gated graphene field-effect transistors. Nature Nanotechnol. 3, 654–659 (2008)

    ADS  CAS  Article  Google Scholar 

  12. Lin, Y. M. et al. Dual-gate graphene FETs with f(T) of 50 GHz. IEEE Electron Device Lett. 31, 68–70 (2010)

    ADS  CAS  Article  Google Scholar 

  13. Lin, Y. M. et al. 100-GHz transistors from wafer-scale epitaxial graphene. Science 327, 662 (2010)

    ADS  CAS  Article  Google Scholar 

  14. Meric, I., Baklitskaya, N., Kim, P. & Shepard, K. L. in Proc. Electronic Devices Meeting 2008, 10.1109/IEDM.2008.4796738 (IEEE, 2008)

    Google Scholar 

  15. Farmer, D. B. et al. Utilization of a buffered dielectric to achieve high field-effect carrier mobility in graphene transistors. Nano Lett. 9, 4474–4478 (2009)

    ADS  CAS  Article  Google Scholar 

  16. Jeon, D. Y. et al. Radio-frequency electrical characteristics of single layer graphene. Jpn. J. Appl. Phys. 48, 091601 (2009)

    ADS  Article  Google Scholar 

  17. Lin, Y. M. et al. Operation of graphene transistors at gigahertz frequencies. Nano Lett. 9, 422–426 (2009)

    ADS  CAS  Article  Google Scholar 

  18. Moon, J. S. et al. Epitaxial-graphene RF field-effect transistors on Si-face 6H-SiC substrates. IEEE Electron Device Lett. 30, 650–652 (2009)

    ADS  CAS  Article  Google Scholar 

  19. Lee, B. K. et al. Conformal Al2O3 dielectric layer deposited by atomic layer deposition for graphene-based nanoelectronics. Appl. Phys. Lett. 92, 203102 (2008)

    ADS  Article  Google Scholar 

  20. Wang, X. R., Tabakman, S. M. & Dai, H. J. Atomic layer deposition of metal oxides on pristine and functionalized graphene. J. Am. Chem. Soc. 130, 8152–8153 (2008)

    CAS  Article  Google Scholar 

  21. Xuan, Y. et al. Atomic-layer-deposited nanostructures for graphene-based nanoelectronics. Appl. Phys. Lett. 92, 013101 (2008)

    ADS  Article  Google Scholar 

  22. Murali, R., Yang, Y. X., Brenner, K., Beck, T. & Meindl, J. D. Breakdown current density of graphene nanoribbons. Appl. Phys. Lett. 94, 243114 (2009)

    ADS  Article  Google Scholar 

  23. Ni, Z. H. et al. Tunable stress and controlled thickness modification in graphene by annealing. ACS Nano 2, 1033–1039 (2008)

    CAS  Article  Google Scholar 

  24. Liao, L. et al. High-kappa oxide nanoribbons as gate dielectrics for high mobility top-gated graphene transistors. Proc. Natl Acad. Sci. USA 107, 6711–6715 (2010)

    ADS  CAS  Article  Google Scholar 

  25. Liao, L. et al. Top-gated graphene nanoribbon transistors with ultrathin high-k dielectrics. Nano Lett. 10, 1917–1921 (2010)

    ADS  CAS  Article  Google Scholar 

  26. Liao, L. et al. High-performance top-gated graphene-nanoribbon transistors using zirconium oxide nanowires as high-dielectric-constant gate dielectrics. Adv. Mater. 22, 1941–1945 (2010)

    CAS  Article  Google Scholar 

  27. Seo, K. et al. Composition-tuned ConSi nanowires: location-selective simultaneous growth along temperature gradient. ACS Nano 3, 1145–1150 (2009)

    CAS  Article  Google Scholar 

  28. Lemme, M. C., Echtermeyer, T. J., Baus, M. & Kurz, H. A graphene field-effect device. IEEE Electron Device Lett. 28, 282–284 (2007)

    ADS  CAS  Article  Google Scholar 

  29. Kim, D. H. & del Alamo, J. A. 30-nm InAs pseudomorphic HEMTs on an InP substrate with a current-gain cutoff frequency of 628 GHz. IEEE Electron Device Lett. 29, 830–833 (2008)

    ADS  CAS  Article  Google Scholar 

  30. Sze, S. M. & Ng, K. K. Physics of Semiconductor Devices 347–349 (Wiley-Interscience, 2007)

    Google Scholar 

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We thank A. Jooyaie and S. Martin for discussions. We also acknowledge the Electron Imaging Center for Nanomachines at UCLA for TEM technical support and the Nanoelectronics Research Facility at UCLA for device fabrication technical support. X.D. acknowledges financial support by the NSF CAREER award 0956171 and the NIH Director’s New Innovator Award Program, part of the NIH Roadmap for Medical Research, through grant number 1DP2OD004342-01.

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Authors and Affiliations



X.D conceived the research. X.D. and L.L. designed the experiments. L.L. performed all the experiments (including material synthesis, device fabrication, and d.c. and radio-frequency characterization) and data analysis. Y.-C.L. contributed to material synthesis, material and device structure characterization, and radio-frequency analysis. M.B. contributed to radio-frequency characterization and analysis. R.C. and Y.L. contributed to d.c. and radio-frequency analysis. J.B. contributed to device fabrication. Y.Q. contributed to material synthesis. X.D. and L.L. co-wrote the paper. All authors discussed the results and commented on the manuscript.

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Correspondence to Xiangfeng Duan.

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The authors declare no competing financial interests.

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This file contains Supplementary Methods, Supplementary Figures 1-8 with legends, Supplementary Tables 1-2 and additional references. (PDF 609 kb)

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Liao, L., Lin, YC., Bao, M. et al. High-speed graphene transistors with a self-aligned nanowire gate. Nature 467, 305–308 (2010).

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