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Enhanced thermoelectric performance of rough silicon nanowires

Nature volume 451, pages 163–167 (2008)Cite this article

Abstract

Approximately 90 per cent of the world’s power is generated by heat engines that use fossil fuel combustion as a heat source and typically operate at 30–40 per cent efficiency, such that roughly 15 terawatts of heat is lost to the environment. Thermoelectric modules could potentially convert part of this low-grade waste heat to electricity. Their efficiency depends on the thermoelectric figure of merit ZT of their material components, which is a function of the Seebeck coefficient, electrical resistivity, thermal conductivity and absolute temperature. Over the past five decades it has been challenging to increase ZT > 1, since the parameters of ZT are generally interdependent1. While nanostructured thermoelectric materials can increase ZT > 1 (refs 2–4), the materials (Bi, Te, Pb, Sb, and Ag) and processes used are not often easy to scale to practically useful dimensions. Here we report the electrochemical synthesis of large-area, wafer-scale arrays of rough Si nanowires that are 20–300 nm in diameter. These nanowires have Seebeck coefficient and electrical resistivity values that are the same as doped bulk Si, but those with diameters of about 50 nm exhibit 100-fold reduction in thermal conductivity, yielding ZT = 0.6 at room temperature. For such nanowires, the lattice contribution to thermal conductivity approaches the amorphous limit for Si, which cannot be explained by current theories. Although bulk Si is a poor thermoelectric material, by greatly reducing thermal conductivity without much affecting the Seebeck coefficient and electrical resistivity, Si nanowire arrays show promise as high-performance, scalable thermoelectric materials.

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Figure 1: Structural characterization of the rough silicon nanowires.
Figure 2: Thermal conductivity of the rough silicon nanowires.
Figure 3: Thermoelectric properties and ZT calculation for the rough silicon nanowire.

References

  1. Majumdar, A. Thermoelectricity in semiconductor nanostructures. Science 303, 777–778 (2004)

    Article  CAS  Google Scholar 

  2. Hsu, K. F. et al. Cubic AgPbmSbTe2+m: bulk thermoelectric materials with high figure of merit. Science 303, 818–821 (2004)

    Article  ADS  CAS  Google Scholar 

  3. Harman, T. C., Taylor, P. J., Walsh, M. P. & LaForge, B. E. Quantum dot superlattice thermoelectric materials and devices. Science 297, 2229–2232 (2002)

    Article  ADS  CAS  Google Scholar 

  4. Venkatasubramanian, R., Siivola, E., Colpitts, T. & O’Quinn, B. Thin-film thermoelectric devices with high room-temperature figures of merit. Nature 413, 597–602 (2001)

    Article  ADS  CAS  Google Scholar 

  5. Touloukian, Y. S., Powell, R. W., Ho, C. Y. & Klemens, P. G. Thermal Conductivity: Metallic Elements and Alloys, Thermophysical Properties of Matter Vol. 1 339 (IFI/Plenum, New York, 1970)

    Book  Google Scholar 

  6. Weber, L. & Gmelin, E. Transport properties of silicon. Appl. Phys. A 53, 136–140 (1991)

    Article  ADS  Google Scholar 

  7. Nolas, G. S., Sharp, J. & Goldsmid, H. J. in Thermoelectrics: Basic Principles and New Materials Development (eds Nolas, G. S., Sharp, J. & Goldsmid, H. J.) Ch. 3 (Springer, Berlin, 2001)

    Book  Google Scholar 

  8. Asheghi, M., Leung, Y. K., Wong, S. S. & Goodson, K. E. Phonon-boundary scattering in thin silicon layers. Appl. Phys. Lett. 71, 1798–1800 (1997)

    Article  ADS  CAS  Google Scholar 

  9. Asheghi, M., Touzelbaev, M. N., Goodson, K. E., Leung, Y. K. & Wong, S. S. Temperature-dependent thermal conductivity of single-crystal silicon layers in SOI substrates. J. Heat Transf. 120, 30–36 (1998)

    Article  CAS  Google Scholar 

  10. Ju, Y. S. & Goodson, K. E. Phonon scattering in silicon films with thickness of order 100 nm. Appl. Phys. Lett. 74, 3005–3007 (1999)

    Article  ADS  CAS  Google Scholar 

  11. Peng, K. Q., Yan, Y. J., Gao, S. P. & Zhu, J. Synthesis of large-area silicon nanowire arrays via self-assembling nanochemistry. Adv. Mater. 14, 1164–1167 (2002)

    Article  CAS  Google Scholar 

  12. Peng, K., Yan, Y., Gao, S. & Zhu, J. Dendrite-assisted growth of silicon nanowires in electroless metal deposition. Adv. Funct. Mater. 13, 127–132 (2003)

    Article  CAS  Google Scholar 

  13. Peng, K. et al. Uniform, axial-orientation alignment of one-dimensional single-crystal silicon nanostructure arrays. Angew. Chem. Intl Edn. 44, 2737–2742 (2005)

    Article  CAS  Google Scholar 

  14. Li, D. et al. Thermal conductivity of individual silicon nanowires. Appl. Phys. Lett. 83, 2934–2936 (2003)

    Article  ADS  CAS  Google Scholar 

  15. Hochbaum, A. I., Fan, R., He, R. & Yang, P. Controlled growth of Si nanowire arrays for device integration. Nano Lett. 5, 457–460 (2005)

    Article  ADS  CAS  Google Scholar 

  16. Ashcroft, N. W. & Mermin, N. D. Solid State Physics Chs 1, 2 and 13 (Saunders College Publishing, Fort Worth, 1976)

    MATH  Google Scholar 

  17. Sze, S. M. Physics of Semiconductor Devices Ch. 1 (John Wiley & Sons, New York, 1981)

    Google Scholar 

  18. Shi, L. et al. Measuring thermal and thermoelectric properties of one-dimensional nanostructures using a microfabricated device. J. Heat Transf. 125, 881–888 (2003)

    Article  CAS  Google Scholar 

  19. Kim, W. et al. Thermal conductivity reduction and thermoelectric figure of merit increase by embedding nanoparticles in crystalline semiconductors. Phys. Rev. Lett. 96, 045901 (2006)

    Article  ADS  Google Scholar 

  20. Zou, J. & Balandin, A. Phonon heat conduction in a semiconductor nanowire. J. Appl. Phys. 89, 2932–2938 (2001)

    Article  ADS  CAS  Google Scholar 

  21. Saha, S., Shi, L. & Prasher, R. Monte Carlo simulation of phonon backscattering in a nanowire. Proc. ASME Int. Mech. Eng. Congr. Exp. (5–10 November 2006) art. no. 15668 1–5 (ASME, Chicago, 2006)

    Google Scholar 

  22. Rowe, D. M. CRC Handbook of Thermoelectrics Ch. 5 (CRC Press, Boca Raton, 1995)

    Book  Google Scholar 

  23. Brinson, M. E. & Dunstan, W. Thermal conductivity and thermoelectric power of heavily doped n-type silicon. J. Phys. C 3, 483–491 (1970)

    Article  ADS  CAS  Google Scholar 

  24. Ruf, T. et al. Thermal conductivity of isotopically enriched silicon. Solid State Commun. 115, 243–247 (2000)

    Article  ADS  CAS  Google Scholar 

  25. Cahill, D. G. & Pohl, R. O. Thermal conductivity of amorphous solids above the plateau. Phys. Rev. B 35, 4067–4073 (1987)

    Article  ADS  CAS  Google Scholar 

  26. Cahill, D. G., Watson, S. K. & Pohl, R. O. Lower limit to the thermal conductivity of disordered crystals. Phys. Rev. B 46, 6131–6140 (1992)

    Article  CAS  Google Scholar 

  27. Mingo, N., Yang, L., Li, D. & Majumdar, A. Predicting the thermal conductivity of Si and Ge nanowires. Nano Lett. 3, 1713–1716 (2003)

    Article  ADS  CAS  Google Scholar 

Download references

Acknowledgements

We thank T.-J. King-Liu and C. Hu for discussions and J. Goldberger for TEM analysis. We acknowledge the support of the Division of Materials Sciences and Engineering, Office of Basic Energy Sciences, DOE. A.I.H. and R.C. thank the NSF-IGERT and ITRI-Taiwan programs, respectively, for fellowship support. We also thank the National Center for Electron Microscopy and the UC Berkeley Microlab for the use of their facilities. R.D.D. thanks the GenCat/Fulbright programme for support.

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Author notes

  1. Allon I. Hochbaum and Renkun Chen: These authors contributed equally to this work.

Authors and Affiliations

  1. Department of Chemistry,,

    Allon I. Hochbaum, Raul Diaz Delgado, Wenjie Liang, Erik C. Garnett & Peidong Yang

  2. Department of Mechanical Engineering,,

    Renkun Chen & Arun Majumdar

  3. Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA,

    Mark Najarian, Arun Majumdar & Peidong Yang

  4. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA,

    Arun Majumdar & Peidong Yang

Authors
  1. Allon I. Hochbaum
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  2. Renkun Chen
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  4. Wenjie Liang
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Corresponding authors

Correspondence to Arun Majumdar or Peidong Yang.

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Supplementary Information

The file contains Supplementary Methods and Discussion; and Supplementary Figures S1-S4 with Legends. (PDF 442 kb)

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Hochbaum, A., Chen, R., Delgado, R. et al. Enhanced thermoelectric performance of rough silicon nanowires. Nature 451, 163–167 (2008). https://doi.org/10.1038/nature06381

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