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bioRxiv · 10.64898/2026.06.23.733868

A Thin Film Transistor Backplane for Scalable Chronic Neural Interfaces

Bourhis, A. M.·Vatsyayan, R.·Tonsfeldt, K. J.·Galton, I.·Dayeh, S. A.
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Abstract

Scaling neural interfaces to ever-higher channel counts has accelerated rapidly with advances in thin-film fabrication, lithography, and connectorization, enabling passive arrays to reach thousands of channels and chart credible pathways to much larger formats. Integrating active electronics directly at the sensing sites offers a complementary route to higher channel density by reducing the number of interconnects required to access large arrays. Here we introduce a monolithic flexible thin-film integrated circuit platform for active neural sensing, inspired by active-matrix display technology. The system integrates dual-gate amorphous indium gallium zinc oxide transistors on polyimide substrates to implement in-pixel transconductance amplification and row-column time-division multiplexing, improving scability for high-channel-count applications. Co-optimization of device architecture, contact engineering, and a hybrid ceramic-polymer thin-film encapsulation yields stable operation with projected lifetimes exceeding 38 years under accelerated aging. In acute and chronic in vivo rat studies, the platform exhibits negligible thermal burden, robust sensory-evoked recordings, and stable functionality over 30 days despite tissue encapsulation. These results establish display-inspired flexible thin-film electronics as a scalable building block for next-generation neural interfaces.

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Bourhis, A. M., Vatsyayan, R., Tonsfeldt, K. J., Galton, I., Dayeh, S. A.. 2026-06-24. A Thin Film Transistor Backplane for Scalable Chronic Neural Interfaces. https://doi.org/10.64898/2026.06.23.733868

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