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Electronic functionalization of the surface of organic semiconductors with self-assembled monolayers

Nature Materials volume 7, pages 8489 (2008) | Download Citation

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Abstract

Self-assembled monolayers (SAMs) are widely used in a variety of emerging applications for surface modification of metals and oxides. Here, we demonstrate a new type of molecular self-assembly: the growth of organosilane SAMs at the surface of organic semiconductors. Remarkably, SAM growth results in a pronounced increase of the surface conductivity of organic materials, which can be very large for SAMs with a strong electron-withdrawing ability. For example, the conductivity induced by perfluorinated alkyl silanes in organic molecular crystals approaches 10−5 S per square, two orders of magnitude greater than the maximum conductivity typically achieved in organic field-effect transistors. The observed large electronic effect opens new opportunities for nanoscale surface functionalization of organic semiconductors with molecular self-assembly. In particular, SAM-induced conductivity shows sensitivity to different molecular species present in the environment, which makes this system very attractive for chemical sensing applications.

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Acknowledgements

We thank A. Zakhidov, J. E. Anthony, E. Garfunkel and Y. Chabal for helpful discussions and S.-W. Cheong and S. Park for technical assistance with AFM. This work has been supported by the NSF grants DMR-0405208 and ECS-0437932.

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  1. Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA

    • M. F. Calhoun
    • , J. Sanchez
    • , D. Olaya
    • , M. E. Gershenson
    •  & V. Podzorov

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Correspondence to V. Podzorov.

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https://doi.org/10.1038/nmat2059

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