A Fully MOTFT-Based Tactile Sensing and Amplifying System

Thin-film transistor (TFT) piezoelectric sensors are widely used in medical electronics, but many studies focus only on the performance of the sensors while neglecting research on TFT-based amplifiers. Therefore, simultaneously implementing sensors and circuits with metal oxide TFTs (MOTFTs) is conducive to promoting their integration and medical application. In this study, we present a fully tactile sensing and amplifying system based on MOTFT. We fabricate a high-performance dual-gate TFT (DGTFT) as a sensor. This DGTFT has high mobility (35.3 cm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>V<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup>s<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup>), excellent top-gate control ability (1.2 V / V), and a high on/off current ratio (6×10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">8</sup>). The TFT amplifier is implemented using a simple single-gate TFT (SGTFT). This amplifier shows a high gain (42.7 dB), a low power consumption (0.31 mW), and a low noise (27.3 uV<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rms</sub> (1-200 Hz)). This system can detect tangible signals like lifting legs, and clenching fists and subtle signals like pulses. This system requires neither complex composite materials nor intricate sensor structures, demonstrating significant potential in personalized identification, human-computer interaction, and healthcare monitoring.