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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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).
Sekitani, T. et al. A rubberlike stretchable active matrix using elastic conductors. Science 321, 1468–1472 (2008).
Wagner, S. et al. Electronic skin: Architecture and components. Physica E 25, 326–334 (2004).
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).
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).
Bao, Z. & Locklin, J. Organic Field-Effect Transistors (CRC Press, 2007).
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).
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).
Voorthuyzen, J. A., Bergveld, P. & Sprenkels, A. J. Semiconductor-based electret sensors for sound and pressure. IEEE Trans. Electr. Insul. 24, 267–276 (1989).
Olthuis, W. Chemical and physical FET-based sensors or variations on an equation. Sens. Actuat. B 105, 96–103 (2005).
Hussain, M., Choa, Y-H. & Niihara, K. Conductive rubber materials for pressure sensors. J. Mater. Sci. Lett. 20, 525–527 (2001).
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).
Engel, J., Chen, J., Chen, N., Pandya, S. & Liu, C. 19th International Conference on MEMS, Istanbul, Turkey (IEEE, 2006).
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).
Metzger, C. et al. Flexible-foam-based capacitive sensor arrays for object detection at low cost. Appl. Phys. Lett. 92, 013506 (2008).
Lee, I. & Sung, H. J. Development of an array of pressure sensors with PVDF film. Exp. Fluids 26, 27–35 (1999).
Shirinov, A. V. & Schomburg, W. K. Pressure sensor from a PVDF film. Sens. Actuat. A 142, 48–55 (2008).
Graz, I. et al. Flexible ferroelectret field-effect transistor for large-area sensor skins and microphones. Appl. Phys. Lett. 89, 073501 (2006).
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).
Darlinski, G. et al. Mechanical force sensors using organic thin-film transistors. J. Appl. Phys. 97, 093708 (2005).
Manunza, I., Sulis, A. & Bonfiglio, A. Pressure sensing by flexible, organic, field effect transistors. Appl. Phys. Lett. 89, 143502 (2006).
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).
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).
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).
Sundar, V. C. et al. Elastomeric transistor stamps: Reversible probing of charge transport in organic crystals. Science 303, 1644–1646 (2004).
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).
Reese, C. & Bao, Z. Organic single-crystal field-effect transistors. Mater. Today 10, 20–27 (2007).
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.
A patent application is in the process of being filed. No patent was initiated prior to and at the time of the submission of the paper.
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Mannsfeld, S., Tee, B., Stoltenberg, R. et al. Highly sensitive flexible pressure sensors with microstructured rubber dielectric layers. Nature Mater 9, 859–864 (2010) doi:10.1038/nmat2834
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