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Nanoscale Joule heating, Peltier cooling and current crowding at graphene–metal contacts

Abstract

The performance and scaling of graphene-based electronics1 is limited by the quality of contacts between the graphene and metal electrodes2,3,4. However, the nature of graphene–metal contacts remains incompletely understood. Here, we use atomic force microscopy to measure the temperature distributions at the contacts of working graphene transistors with a spatial resolution of 10 nm (refs 5, 6, 7, 8), allowing us to identify the presence of Joule heating9,10,11, current crowding12,13,14,15,16 and thermoelectric heating and cooling17. Comparison with simulation enables extraction of the contact resistivity (150–200 Ω µm2) and transfer length (0.2–0.5 µm) in our devices; these generally limit performance and must be minimized. Our data indicate that thermoelectric effects account for up to one-third of the contact temperature changes, and that current crowding accounts for most of the remainder. Modelling predicts that the role of current crowding will diminish and the role of thermoelectric effects will increase as contacts improve.

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Figure 1: Device layout.
Figure 2: Measured and predicted contact heating and cooling.
Figure 3: Relative contribution of contact effects.
Figure 4: Contact temperature under varying conditions.

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References

  1. Schwierz, F. Graphene transistors. Nature Nanotech. 5, 487–496 (2010).

    Article  CAS  Google Scholar 

  2. Nagashio, K., Nishimura, T., Kita, K. & Toriumi, A. Systematic investigation of the intrinsic channel properties and contact resistance of monolayer and multilayer graphene field-effect transistor. Jpn J. Appl. Phys. 49, 051304 (2010).

    Article  Google Scholar 

  3. Nagashio, K., Nishimura, T., Kita, K. & Toriumi, A. Contact resistivity and current flow path at metal/graphene contact. Appl. Phys. Lett. 97, 143514 (2010).

    Article  Google Scholar 

  4. Khomyakov, P. A., Starikov, A. A., Brocks, G. & Kelly, P. J. Nonlinear screening of charges induced in graphene by metal contacts. Phys. Rev. B 82, 115437 (2010).

    Article  Google Scholar 

  5. Varesi, J. & Majumdar, A. Scanning Joule expansion microscopy at nanometer scales. Appl. Phys. Lett. 72, 37–39 (1998).

    Article  CAS  Google Scholar 

  6. Majumdar, A. & Varesi, J. Nanoscale temperature distributions measured by scanning Joule expansion microscopy. J. Heat Transfer 120, 297–305 (1998).

    Article  CAS  Google Scholar 

  7. Cannaerts, M., Buntinx, D., Volodin, A. & Van Haesendonck, C. Calibration of a scanning Joule expansion microscope (SJEM). Appl. Phys. A 72, S67–S70 (2001).

    Article  Google Scholar 

  8. Gurrum, S. P., King, W. P., Joshi, Y. K. & Ramakrishna, K. Size effect on the thermal conductivity of thin metallic films investigated by scanning Joule expansion microscopy. J. Heat Transfer 130, 082403 (2008).

    Article  Google Scholar 

  9. Pop, E. Energy dissipation and transport in nanoscale devices. Nano Res. 3, 147–169 (2010).

    Article  CAS  Google Scholar 

  10. Dorgan, V. E., Bae, M-H. & Pop, E. Mobility and saturation velocity in graphene on SiO2 . Appl. Phys. Lett. 97, 082112 (2010).

    Article  Google Scholar 

  11. Bae, M-H., Ong, Z-Y., Estrada, D. & Pop, E. Imaging, simulation, and electrostatic control of power dissipation in graphene devices. Nano Lett. 10, 4787–4793 (2010).

    Article  CAS  Google Scholar 

  12. Jackson, R. & Graham, S. Specific contact resistance at metal/carbon nanotube interfaces. Appl. Phys. Lett. 94, 012109 (2009).

    Article  Google Scholar 

  13. Lan, C. et al. Measurement of metal/carbon nanotube contact resistance by adjusting contact length using laser ablation. Nanotechnology 19, 125703 (2008).

    Article  Google Scholar 

  14. Franklin, A. D. & Chen, Z. Length scaling of carbon nanotube transistors. Nature Nanotech. 5, 858–862 (2010).

    Article  CAS  Google Scholar 

  15. Schroder, D. K. Semiconductor Material and Device Characterization (Wiley, 2006).

    Google Scholar 

  16. Chieh, Y. S., Perera, A. K. & Krusius, J. P. Series resistance of silicided ohmic contacts for nanoelectronics. IEEE Trans. Electron. Dev. 39, 1882–1888 (1992).

    Article  CAS  Google Scholar 

  17. DiSalvo, F. J. Thermoelectric cooling and power generation. Science 285, 703–706 (1999).

    Article  CAS  Google Scholar 

  18. Schroder, D. K. & Babcock, J. A. Negative bias temperature instability: road to cross in deep submicron silicon semiconductor manufacturing. J. Appl. Phys. 94, 1–18 (2003).

    Article  CAS  Google Scholar 

  19. Freitag, M., Chiu, H-Y., Steiner, M., Perebeinos, V. & Avouris, P. Thermal infrared emission from biased graphene. Nature Nanotech. 5, 497–501 (2010).

    Article  CAS  Google Scholar 

  20. Xu, X., Gabor, N. M., Alden, J. S., van der Zande, A. M. & McEuen, P. L. Photo-thermoelectric effect at a graphene interface junction. Nano Lett. 10, 562–566 (2009).

    Article  Google Scholar 

  21. Wei, P., Bao, W., Pu, Y., Lau, C. N. & Shi, J. Anomalous thermoelectric transport of Dirac particles in graphene. Phys. Rev. Lett. 102, 166808 (2009).

    Article  Google Scholar 

  22. Zuev, Y. M., Chang, W. & Kim, P. Thermoelectric and magnetothermoelectric transport measurements of graphene. Phys. Rev. Lett. 102, 096807 (2009).

    Article  Google Scholar 

  23. Checkelsky, J. G. & Ong, N. P. Thermopower and Nernst effect in graphene in a magnetic field. Phys. Rev. B 80, 081413 (2009).

    Article  Google Scholar 

  24. Zhu, W., Perebeinos, V., Freitag, M. & Avouris, P. Carrier scattering, mobilities, and electrostatic potential in monolayer, bilayer, and trilayer graphene. Phys. Rev. B 80, 235402 (2009).

    Article  Google Scholar 

  25. International Technology Roadmap for Semiconductors (ITRS), http://public.itrs.net (2009).

  26. Thompson, S. E. et al. In search of ‘Forever,’ continued transistor scaling one new material at a time. IEEE Trans. Semicond. Manuf. 18, 26–36 (2005).

    Article  Google Scholar 

  27. Ishigami, M., Chen, J. H., Cullen, W. G., Fuhrer, M. S. & Williams, E. D. Atomic structure of graphene on SiO2 . Nano Lett. 7, 1643–1648 (2007).

    Article  CAS  Google Scholar 

  28. Koh, Y. H., Bae, M.-H., Cahill, D. G. & Pop, E . Reliably counting atomic planes of few-layer graphene (n > 4). ACS Nano 5, 269–274 (2011).

    Article  CAS  Google Scholar 

  29. Malard, L. M., Pimenta, M. A., Dresselhaus, G. & Dresselhaus, M. S. Raman spectroscopy in graphene. Phys. Rep. 473, 51–87 (2009).

    Article  CAS  Google Scholar 

  30. Silvestrov, P. G. & Efetov, K. B. Charge accumulation at the boundaries of a graphene strip induced by a gate voltage: electrostatic approach. Phys. Rev. B 77, 155436 (2008).

    Article  Google Scholar 

  31. Vasko, F. T. & Zozoulenko, I. V. Conductivity of a graphene strip: width and gate-voltage dependencies. Appl. Phys. Lett. 97, 092115 (2010).

    Article  Google Scholar 

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Acknowledgements

This work was supported by the Air Force Office of Scientific Research MURI FA9550-08-1-0407, Office of Naval Research grants N00014-07-1-0767, N00014-09-1-0180 and N00014-10-1-0061, and the Air Force Young Investigator Program (E.P.).

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Contributions

K.L.G. performed measurements and simulations. M-H.B. fabricated devices and assisted with simulations. E.P. implemented the computational model and physical interpretation, with help from F.L., while E.P. and W.P.K. conceived the experiments. All authors discussed the results. K.L.G., E.P. and W.P.K. co-wrote the manuscript.

Corresponding authors

Correspondence to Eric Pop or William P. King.

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The authors declare no competing financial interests.

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Grosse, K., Bae, MH., Lian, F. et al. Nanoscale Joule heating, Peltier cooling and current crowding at graphene–metal contacts. Nature Nanotech 6, 287–290 (2011). https://doi.org/10.1038/nnano.2011.39

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