Flexible Piezoelectric-Coupling\nOrganic Transistor-Based\nPress Sensors with Ferroelectric Charge-Transfer Complex Integrated\nDielectrics

The\ndevelopment of flexible tactile sensors is critical\nfor wearable\nelectronics and human–computer interfaces. The porous structure\nand floating gate strategy in organic transistors are not easy to\ncontrol and usually lead to a relatively large detection limit. To\novercome these issues, effectively combining the piezoelectric effect\ninto transistors in a simple way enhances the capacitance sensing\nand amplifies the readout characteristics. In this paper, solution-processed\ntransistor-based pressure sensors were fabricated by using polar organic\ncharge-transfer complex/dielectric polymer blend solutions. The hybrid\ndielectrics integrate well-distributed ferroelectric micro-/nanoparticles\nvia tuning the doping ratio and exhibit a good insulating property.\nThe devices presented a pressure sensitivity of 3.2 kPa<sup>–1</sup>, good durability, and a low detection limit of 0.01 kPa. Moreover,\nthe sensors were successfully introduced to build a sensor-robotic\ncontrol system, switch, and haptic array keyboard. The well-integrated\ndielectric design method provides a simple and powerful way to construct\nflexible pressure sensors with great potential.