Flexible and high sensitive capacitive pressure sensor with microstructured electrode inspired by ginkgo leaf

Abstract A reasonable design of flexible pressure sensors is one of the necessary conditions for improving the sensing performance and meeting the demands of various application fields, including intelligent robot, human–machine interface and health monitoring. Herein, the template method is adopted to replicate the unique natural surface microstructure of ginkgo leaf based on the concept of bionics, and a microstructured copper/polydimethylsiloxane electrode is fabricated by the magnetron sputtering method. In addition, a porous carbon black/thermoplastic polyurethane film is used as the intermediate layer to reduce the hysteresis of the sensor. The capacitive pressure sensor exhibits a high sensitivity (1.194 kPa −1 , <1 kPa), wide pressure detection range (0–300 kPa), fast response time (80 ms), low hysteresis (maximum to 6.58%), ultra-low detection limit (6.53 Pa), and high stability. Further, we demonstrate the practical applications of the sensor in human joint motion and pulse signal detection, walking state detection, and providing tactile feedback during grasping with hand prosthesis. The experimental results indicate that the proposed capacitive pressure sensor can be potentially applied in the fields of electronic skin, wearable devices, and smart prostheses.