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An elastic and reconfigurable synaptic transistor based on a stretchable bilayer semiconductor

Abstract

Neurons of the ventral tegmental area of the brain contain single axon terminals that release excitatory and inhibitory neurotransmitters, creating reconfigurable synaptic behaviour. Artificial synaptic transistors that exhibit similar excitatory and inhibitory behaviour—and hence synaptic function reconfiguration—could provide diverse functionality and efficient computing in various applications. However, some of these applications, such as soft robotics and wearable electronics, require synaptic devices that are mechanically soft and deformable. Here we report an elastic and reconfigurable synaptic transistor that exhibits inhibitory and excitatory characteristics even under mechanical strain. The synaptic device uses a top-gated configuration and is made using a stretchable bilayer semiconductor and an encapsulating elastomer as the gate dielectric. The device exhibits memory characteristics when operating with a presynaptic pulse of only 80 mV, resulting in a low specific energy consumption. When applied to a model artificial neural network for dual-directional image recognition of the Modified National Institute of Standards and Technology dataset, a recognition accuracy of over 90% is achieved even when the transistors are stretched by 50%.

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Fig. 1: Overview of the stretchable reconfigurable synaptic transistor.
Fig. 2: Thin, stretchable N2200 n-type semiconductor film.
Fig. 3: Stretchable synaptic transistor based on the N2200 thin film.
Fig. 4: Stretchable synaptic transistor based on the s-CNT network.
Fig. 5: Stretchable reconfigurable synaptic transistor based on bilayer semiconductors.
Fig. 6: Dual-directional image recognition.

Data availability

The data that support the findings of this study or additional data related to this paper are available from the corresponding author upon request.

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Acknowledgements

C.Y. would like to acknowledge financial support from the Office of Naval Research grant (N00014-18-1-2338) under the Young Investigator Program, as well as the National Science Foundation grants of CAREER (1554499), EFRI (1935291) and CPS (1931893 and 2227062). T.J.M. and A.F. acknowledge support from the Air Force Office of Scientific Research grant (FA9550-18-1-0320 and FA9550-22-1-0423) and the Northwestern University MRSEC grant National Science Foundation DMR (1720139).

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H.S. and C.Y. conceived and designed the research. H.S., S.P. and Y.Z. performed the experiments. H.S. and C.Y. analysed the data. H.S. and F.E. performed the simulation work. B.W., Z.C., T.J.M. and A.F. provided the materials and advised on the experiment. H.S. and C.Y. wrote the manuscript. All the authors revised the manuscript.

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Correspondence to Cunjiang Yu.

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Nature Electronics thanks Huipeng Chen, Zheng Yan and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Shim, H., Ershad, F., Patel, S. et al. An elastic and reconfigurable synaptic transistor based on a stretchable bilayer semiconductor. Nat Electron 5, 660–671 (2022). https://doi.org/10.1038/s41928-022-00836-5

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