Highly sensitive ionic pressure sensor based on concave meniscus for electronic skin

Flexible pressure sensing plays a critical role in the human–machine interaction; therefore highly sensitive pressure sensors have promising potential in such applications. Capacitive pressure sensors have inherent attributes of simple configuration and fast response time. However, the existing applications of sensors are limited by the limited sensitivity as well as complex manufacturing. Herein, a highly sensitive ionic pressure sensor with the microstructured dielectric layer has been proposed. The polycarbonate membrane is used as the template to manufacture the microstructure of the concave meniscus. By packing the top electrode, dielectric layer and bottom electrode, the ionic pressure sensor is fabricated. The sensor presents a sensitivity of 35.96 k Pa−1 with an excellent robustness of tolerating repeated pressure for at least 200 000 cycles without fatigue. In addition, the response time of the sensor is 21 ms and the limit of detection is 0.61 Pa. The ionic pressure sensor offers a highly sensitive sensing device for robotics and human–machine interaction. Furthermore, the concave meniscus realized by the template-based method provides a novel guideline for other microstructure-enabled devices.