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A wearable in-sensor computing platform based on stretchable organic electrochemical transistors

Nature Electronics volume 7, pages 1176–1185 (2024)Cite this article

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Abstract

Organic electrochemical transistors could be used in in-sensor computing and wearable healthcare applications. However, they lack the conformity and stretchability needed to minimize mechanical mismatch between the devices and human body, are challenging to fabricate at a scale with small feature sizes and high density, and require miniaturized readout systems for practical on-body applications. Here we report a wearable in-sensor computing platform based on stretchable organic electrochemical transistor arrays. The platform offers more than 50% stretchability by using an adhesive supramolecular buffer layer during fabrication that improves robustness at interfaces under strain. We fabricate stretchable transistor arrays with feature sizes down to 100 μm using a high-resolution six-channel inkjet printing system. We also develop a coin-sized data readout system for biosignal acquisition. We show that our coin-sized, smartwatch-compatible electronic module can provide wearable in-sensor edge computing.

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Fig. 1: Design strategy for coin-sized wearable in-sensor computing unit (WISE platform) based on ISOECT arrays.
Fig. 2: Materials strategies for the ISOECT.
Fig. 3: Scalable fabrication of the ISOECT array.
Fig. 4: ISOECT array for neuromorphic computing.
Fig. 5: WISE platform for wearable in-sensor computing.

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Data availability

Data that support the findings of this study are available from the corresponding authors upon reasonable request.

Code availability

The code used for RC is available via GitHub at https://github.com/HKU-WISE-Group/OECT-RC.

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Acknowledgements

We thank P. K. L. Chan, C. Wong, J. Chan and P. S. Yip from the HKU Central Fabrication Lab for support on device fabrication, N. Wong and X. Meng for discussions on the low-power biochips, K. Wu, S. Xue and C. Li for discussions on materials synthesis, and N. Tien and C. K. Chui for generous support on the printing facilities and wet lab resources at Tam Wing Fan Innovation Wing. S.Z. acknowledges the Collaborative Research Fund (C7005-23Y) and the Theme-based Research Scheme (T45-701/22-R) from the Research Grants Council of the Hong Kong SAR Government; Innovation and Technology Fund (Mainland-Hong Kong Joint Funding Scheme, MHP/053/21, MHP/066/20) from the Hong Kong SAR Government; and the Shenzhen-Hong Kong-Macau Technology Research Programme (SGDX20210823103537034) from the Shenzhen Science and Technology Innovation Committee. The PERfECT readout platform is funded by the HKU Innovation Wing Two Research Fund and Technology Start-up Support Scheme for Universities (TSSSU/HKU/23/13).

Author information

Author notes

  1. These authors contributed equally: Dingyao Liu, Xinyu Tian, Jing Bai, Shaocong Wang.

Authors and Affiliations

  1. Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, China

    Dingyao Liu, Xinyu Tian, Jing Bai, Shaocong Wang, Shilei Dai, Yan Wang, Zhongrui Wang & Shiming Zhang

  2. School of Microelectronics, Southern University of Science and Technology, Shenzhen, China

    Zhongrui Wang

  3. State Key Laboratory of Pharmaceutical Biotechnology, The University of Hong Kong, Hong Kong SAR, China

    Shiming Zhang

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  1. Dingyao Liu
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Contributions

S.Z., Z.W. and D.L. conceived the idea. S.Z. acquired funding and supervised the whole research. D.L., X.T., J.B. and S.W. conducted the experiments and collected the data. X.T., J.B. and S.W. contributed to the algorithm design and simulation. S.Z., X.T. and J.B. designed the PERfECT readout system for wearable data analysis. X.T. and J.B. coded the AI-embedded program in PERfECT for in-sensor computing with an ISOECT array. D.L., X.T., J.B. and Y.W. contributed to the fabrication of the ISOECT array. D.L., X.T., Y.W. and S.D. contributed to the ISOECT device characterization. S.Z. and D.L. drafted the manuscript. All authors contributed to revising the manuscript.

Corresponding authors

Correspondence to Zhongrui Wang or Shiming Zhang.

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Liu, D., Tian, X., Bai, J. et al. A wearable in-sensor computing platform based on stretchable organic electrochemical transistors. Nat Electron 7, 1176–1185 (2024). https://doi.org/10.1038/s41928-024-01250-9

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