Piezoelectric ion gated organic electrochemical transistors for efficient vibration sensing and on-site amplification

Accurate detection of physiological vibrations is vital for monitoring health and enabling sensory feedback in bioelectronics. Current technologies often suffer from low signal-to-noise ratios (SNR), bulkiness, and the need for external amplification. Here, we introduce piezoelectric internal ion-gated organic electrochemical transistors (Piezo-IGTs), which efficiently convert mechanical vibrations into amplified electrical signals. These devices integrate laminated P(VDF-TrFE) microfiber films as the gate atop the transistor channel, generating voltage upon deformation to modulate mobile ions in the conducting polymer. Fabricated via sequential deposition and lamination, Piezo-IGTs achieve high fill factors and efficient on-site amplification, improving SNR over standalone piezoelectric films. They operate near 0 V gate voltage, enabling low-power performance. We validate their functionality in mechanomyography, speech recognition, and mechanocardiography using microscale Piezo-IGTs. This self-contained, flexible architecture demonstrates promise for integration into implantable and wearable systems, offering real-time, high-fidelity acquisition of bio-mechanical signals in next-generation health monitoring and neuroprosthetic applications.