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Flexible molecular-scale electronic devices

Abstract

Flexible materials and devices could be exploited in light-emitting diodes1, electronic circuits2,3, memory devices4, sensors5,6, displays7,8, solar cells9 and bioelectronic devices10. Nanoscale elements such as thin films11,12, nanowires13, nanotubes14 and nanoparticles4 can also be incorporated into the active films of mechanically flexible devices. Large-area devices containing extremely thin films of molecular materials15,16 represent the ultimate scaling of flexible devices based on organic materials, but the influence of bending and twisting on the electrical and mechanical stability of such devices has never been examined. Here, we report the fabrication and characterization of two-terminal electronic devices based on self-assembled monolayers of alkyl or aromatic thiol molecules on flexible substrates. We find that the charge transport characteristics of the devices remain stable under severe bending conditions (radius ≤ 1 mm) and a large number of repetitive bending cycles (≥1,000). The devices also remain reliable in various bending configurations, including twisted and helical structures.

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Figure 1: Molecular devices and electrical characteristics under flat conditions.
Figure 2: Stability and retention characteristics of flat devices.
Figure 3: Bending tests for flexible molecular devices.
Figure 4: Flexible molecular devices under twisted and helical conditions.

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Acknowledgements

This work was supported by the National Research Laboratory programme and a Korean National Core Research Centre grant from the Korean Ministry of Education, Science and Technology, and the Research Settlement Fund for new faculty at Seoul National University. The authors thank J-S. Yeo, Y. Gon and S-Y. Lee for experimental assistance.

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Contributions

T.L. planned and supervised the project. S.P. designed and performed the experiments. S.P., G.W., B.C. and T.L. analysed and interpreted the data and wrote the manuscript. Y.K. and S.S. assisted in device fabrication and measurements. Y.J. assisted in the bending experiments. M-H.Y. contributed to discussions throughout the project.

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Correspondence to Takhee Lee.

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The authors declare no competing financial interests.

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Park, S., Wang, G., Cho, B. et al. Flexible molecular-scale electronic devices. Nature Nanotech 7, 438–442 (2012). https://doi.org/10.1038/nnano.2012.81

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