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Vertical, electrolyte-gated organic transistors show continuous operation in the MA cm−2 regime and artificial synaptic behaviour

Nature Nanotechnology (2019) | Download Citation

Abstract

Until now, organic semiconductors have failed to achieve high performance in highly integrated, sub-100 nm transistors. Consequently, single-crystalline materials such as single-walled carbon nanotubes, MoS2 or inorganic semiconductors are the materials of choice at the nanoscale. Here we show, using a vertical field-effect transistor design with a channel length of only 40 nm and a footprint of 2 × 80 × 80 nm2, that high electrical performance with organic polymers can be realized when using electrolyte gating. Our organic transistors combine high on-state current densities of above 3 MA cm−2, on/off current modulation ratios of up to 108 and large transconductances of up to 5,000 S m−1. Given the high on-state currents at such large on/off ratios, our novel structures also show promise for use in artificial neural networks, where they could operate as memristive devices with sub-100 fJ energy usage.

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The raw data that support the plots within this paper and other findings of this study are provided in the Supplementary Information and are available from the authors upon reasonable request.

Additional information

Journal peer review information Nature Nanotechnology thanks Bjorn Lussem and the other anonymous reviewer(s) for their contribution to the peer review of this work.

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Acknowledgements

The authors thank BASF SE for supplying the organic semiconductors and liquid electrolytes. The authors acknowledge partial support by the ‘Solar Technologies go Hybrid’ (SolTech) initiative, the Center for Nanoscience (CeNS) and the Nanosystems Initiative Munich (NIM).

Author information

Author notes

    • Fabio del Giudice

    Present address: Walter-Schottky Institute, Technical University Munich, Garching, Germany

Affiliations

  1. Physics of Nanosystems, Department of Physics, Ludwig-Maximilians-Universität München, Munich, Germany

    • Jakob Lenz
    • , Fabio del Giudice
    • , Fabian R. Geisenhof
    • , Felix Winterer
    •  & R. Thomas Weitz
  2. Nanosystems Initiative Munich (NIM), Munich, Germany

    • R. Thomas Weitz
  3. Center for NanoScience (CeNS), Ludwig-Maximilians-Universität München, Munich, Germany

    • R. Thomas Weitz

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Contributions

J.L. and R.T.W conceived the project. J.L. prepared the VOFET samples and conducted the measurements and data analysis. F.d.G prepared the lateral transistor samples and conducted the measurements and data analysis. All authors discussed the data. J.L. and R.T.W. wrote the manuscript with input from all authors. R.T.W. supervised the project.

Competing interests

J.L. and R.T.W. have submitted a patent application to the German patent office (no. 10 2018 221 361.5) covering the structure of the VOFET and the applications discussed in this manuscript.

Corresponding author

Correspondence to R. Thomas Weitz.

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DOI

https://doi.org/10.1038/s41565-019-0407-0