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Highly sensitive flexible pressure sensors with microstructured rubber dielectric layers

Nature Materials volume 9, pages 859–864 (2010)Cite this article

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Abstract

The development of an electronic skin is critical to the realization of artificial intelligence that comes into direct contact with humans, and to biomedical applications such as prosthetic skin. To mimic the tactile sensing properties of natural skin, large arrays of pixel pressure sensors on a flexible and stretchable substrate are required. We demonstrate flexible, capacitive pressure sensors with unprecedented sensitivity and very short response times that can be inexpensively fabricated over large areas by microstructuring of thin films of the biocompatible elastomer polydimethylsiloxane. The pressure sensitivity of the microstructured films far surpassed that exhibited by unstructured elastomeric films of similar thickness, and is tunable by using different microstructures. The microstructured films were integrated into organic field-effect transistors as the dielectric layer, forming a new type of active sensor device with similarly excellent sensitivity and response times.

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Figure 1: Fabrication of microstructured PDMS films.
Figure 2: Characterization of the capacitive pressure response of microstructured PDMS films.
Figure 3: Pressure response of an organic transistor with a microstructured PDMS dielectric layer.
Figure 4: Plastic and flexible pixel-type pressure-sensor arrays.

References

  1. Someya, T. et al. Conformable, flexible, large-area networks of pressure and thermal sensors with organic transistor active matrixes. Proc. Natl Acad. Sci. 102, 12321–12325 (2005).

    Article  CAS  Google Scholar 

  2. Sekitani, T. et al. A rubberlike stretchable active matrix using elastic conductors. Science 321, 1468–1472 (2008).

    Article  CAS  Google Scholar 

  3. Wagner, S. et al. Electronic skin: Architecture and components. Physica E 25, 326–334 (2004).

    Article  Google Scholar 

  4. Sun, Y., Choi, W. M., Jiang, H., Huang, Y. Y. & Rogers, J. A. Controlled buckling of semiconductor nanoribbons for stretchable electronics. Nature Nanotech. 1, 201–207 (2006).

    CAS  Google Scholar 

  5. Dellon, E. S., Mourey, R. & Dellon, A. L. Human pressure perception values for constant and moving one- and two-point discrimination. J. Plast. Reconstr. Surg. 90, 112–117 (1992).

    Article  CAS  Google Scholar 

  6. Bao, Z. & Locklin, J. Organic Field-Effect Transistors (CRC Press, 2007).

    Book  Google Scholar 

  7. Roberts, M. E. et al. Water-stable organic transistors and their application in chemical and biological sensors. Proc. Natl Acad. Sci. 105, 12134–12139 (2008).

    Article  CAS  Google Scholar 

  8. Someya, T. et al. A large-area, flexible pressure sensor matrix with organic field-effect transistors for artificial skin applications. Proc. Natl Acad. Sci. 101, 9966–9970 (2004).

    Article  CAS  Google Scholar 

  9. Voorthuyzen, J. A., Bergveld, P. & Sprenkels, A. J. Semiconductor-based electret sensors for sound and pressure. IEEE Trans. Electr. Insul. 24, 267–276 (1989).

    Article  CAS  Google Scholar 

  10. Olthuis, W. Chemical and physical FET-based sensors or variations on an equation. Sens. Actuat. B 105, 96–103 (2005).

    Article  CAS  Google Scholar 

  11. Hussain, M., Choa, Y-H. & Niihara, K. Conductive rubber materials for pressure sensors. J. Mater. Sci. Lett. 20, 525–527 (2001).

    Article  CAS  Google Scholar 

  12. Shimojo, M., Namiki, A., Ishikawa, M., Makino, R. & Mabuchi, K. A tactile sensor sheet using pressure conductive rubber with electrical-wires stitched method. IEEE Sensors J. 4, 589–596 (2004).

    Article  Google Scholar 

  13. Engel, J., Chen, J., Chen, N., Pandya, S. & Liu, C. 19th International Conference on MEMS, Istanbul, Turkey (IEEE, 2006).

    Google Scholar 

  14. Lee, H-K., Chang, S-I. & Yoon, E. A flexible polymer tactile sensor: Fabrication and modular expandability for large area deployment. J. Microelectromech. Syst. 15, 1681–1686 (2006).

    Article  CAS  Google Scholar 

  15. Metzger, C. et al. Flexible-foam-based capacitive sensor arrays for object detection at low cost. Appl. Phys. Lett. 92, 013506 (2008).

    Article  Google Scholar 

  16. Lee, I. & Sung, H. J. Development of an array of pressure sensors with PVDF film. Exp. Fluids 26, 27–35 (1999).

    Article  CAS  Google Scholar 

  17. Shirinov, A. V. & Schomburg, W. K. Pressure sensor from a PVDF film. Sens. Actuat. A 142, 48–55 (2008).

    Article  CAS  Google Scholar 

  18. Graz, I. et al. Flexible ferroelectret field-effect transistor for large-area sensor skins and microphones. Appl. Phys. Lett. 89, 073501 (2006).

    Article  Google Scholar 

  19. Graz, I. et al. Flexible active-matrix cells with selectively poled bifunctional polymer–ceramic nanocomposite for pressure and temperature sensing skin. J. Appl. Phys. 106, 034503 (2009).

    Article  Google Scholar 

  20. Darlinski, G. et al. Mechanical force sensors using organic thin-film transistors. J. Appl. Phys. 97, 093708 (2005).

    Article  Google Scholar 

  21. Manunza, I., Sulis, A. & Bonfiglio, A. Pressure sensing by flexible, organic, field effect transistors. Appl. Phys. Lett. 89, 143502 (2006).

    Article  Google Scholar 

  22. Chan, Y., Mi, Y., Trau, D., Huang, P. & Chen, E. Micromolding of PDMS scaffolds and microwells for tissue culture and cell patterning: A new method of microfabrication by the self-assembled micropatterns of diblock copolymer micelles. Polymer 47, 5124–5130 (2006).

    Article  Google Scholar 

  23. Balaban, N. Q. et al. Force and focal adhesion assembly: A close relationship studied using elastic micropatterned substrates. Nature Cell Biol. 3, 466–472 (2001).

    Article  CAS  Google Scholar 

  24. Reese, C., Chung, W-J., Ling, M-M., Roberts, M. E. & Bao, Z. High-performance microscale single-crystal transistors by lithography on an elastomer dielectric. Appl. Phys. Lett. 89, 202108 (2006).

    Article  Google Scholar 

  25. Sundar, V. C. et al. Elastomeric transistor stamps: Reversible probing of charge transport in organic crystals. Science 303, 1644–1646 (2004).

    Article  CAS  Google Scholar 

  26. Kloc, Ch., Simpkins, P. G., Siegrist, T. & Laudise, R. A. Physical vapour growth of centimetre-sized crystals of alpha-hexathiophene. J. Cryst. Growth 182, 416–427 (1997).

    Article  CAS  Google Scholar 

  27. Reese, C. & Bao, Z. Organic single-crystal field-effect transistors. Mater. Today 10, 20–27 (2007).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

The authors thank J. Locklin for discussions. We thank N. Sutardja and J. Opatkiewicz for help during the development of the microstructuring technology and the first sensor prototypes. This project was partially funded by NSF ECCS 0730710 and MURI Office of Naval Research (N000140810654). We thank the Center for Polymer Interface Macromolecular Assemblies (CPIMA) for the use of shared facilities. We also acknowledge the use of the Stanford Nanocharacterization Laboratory and the Stanford Nanofabrication Facility, partially supported by the National Science Foundation through the National Nanotechnology Infrastructure Network. Part of this work was done at the Stanford Synchrotron Radiation Laboratory (SSRL), operated by the Department of Energy. S.C.B.M. acknowledges postdoctoral fellowship support by the Deutsche Forschungsgemeinschaft (DFG) grant MA ∼3342/1-1. B.C-K.T. acknowledges support from a National Science Scholarship from the Agency for Science, Technology and Research (A*STAR), Singapore. R.M.S. acknowledges support from a National Science Foundation Graduate Fellowship. Z.B. acknowledges support from a Sloan Research Fellowship.

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Authors and Affiliations

  1. Department of Chemical Engineering, Stanford University, Stanford, California 94305, USA

    Stefan C. B. Mannsfeld, Christopher V. H-H. Chen, Soumendra Barman, Beinn V. O. Muir, Anatoliy N. Sokolov, Colin Reese & Zhenan Bao

  2. Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA

    Benjamin C-K. Tee

  3. Department of Chemistry, Stanford University, Stanford, California 94305, USA

    Randall M. Stoltenberg

Authors
  1. Stefan C. B. Mannsfeld
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  4. Christopher V. H-H. Chen
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  5. Soumendra Barman
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  9. Zhenan Bao
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Contributions

Z.B. and S.C.B.M. conceptualized and directed the research project. S.C.B.M. developed the first working sensor prototypes. B.C-K.T. developed large portions of the experimental set-ups. S.C.B.M and B.C-K.T. discussed and carried out the majority of the experiments. B.C-K.T. and C.V.H-H.C designed and fabricated the matrix sensor. B.C-K.T. carried out the temperature drift and loading/unloading stability experiments. R.M.S. took the SEM data. S.B. helped with some experiments. R.M.S., B.C-K.T. and B.V.O.M fabricated the Si moulds. B.V.O.M. fabricated the photolithographic mask. A.N.S. and B.C-K.T carried out most of the bending-stability experiments. C.R. and B.C-K.T. grew the rubrene crystals. S.C.B.M. wrote the first draft of the manuscript. All authors discussed the results and commented on the manuscript.

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Correspondence to Zhenan Bao.

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Mannsfeld, S., Tee, BK., Stoltenberg, R. et al. Highly sensitive flexible pressure sensors with microstructured rubber dielectric layers. Nature Mater 9, 859–864 (2010). https://doi.org/10.1038/nmat2834

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