A Fully-Integrated Wearable In-Sensor Computing Platform based on Intrinsically Stretchable Organic Electrochemical Transistors

Organic electrochemical transistors (OECT) have emerged as a promising technology paradigm for in-sensor computing and wearable healthcare applications [1]. However, several major challenges limit their widespread adoption in real-world applications: 1) the lack of conformable and stretchable OECT units to reduce the mechanical mismatch between devices and the soft human body; 2) the lack of reliable fabrication methods to enable scalable manufacturing of intrinsically stretchable OECT arrays with smaller feature sizes and high density; and 3) the lack of miniaturized readout systems to enable wearable-sized assembly [2]. In this work, we present a wearable, integrated, and soft electronic (WISE) platform based on intrinsically stretchable OECT arrays, addressing all these challenges. The WISE-platform achieves: 1) intrinsically stretchability (>50%) by implementing a new material protocol for device assembly and improving strain-robustness at interfaces with a tough adhesive supermolecular buffer layer; 2) a scalable fabrication of stretchable OECTs arrays with feature size down to 100 μm using a high-resolution 6 channel inkjet printing system; and 3) a customized, coin-sized data readout system for easy acquisition of biosignals at their origin. As an example, we demonstrate the use of the coin-sized, smartwatch-compatible electronic module for wearable in-sensor computing at the edge, but other application scenarios can be easily imagined.