High Sensitivity Capacitive Pressure Sensor With Bi-Layer Porous Structure Elastomeric Dielectric Formed by a Facile Solution Based Process

A bi-layer structure elastomeric dielectric film composed of more porous upper part and less porous bottom part was formed with a facile solution based process. The fabricated sensor devices have much improved sensitivity in the subtle, low, and medium pressure ranges, while maintaining sensing performance in the large pressure range. The devices also exhibit fast response and relaxation (less than 20 ms) and an excellent durability. The characterization of the sensor is through a portable low-cost data acquisition circuit board, which enables detection of a tiny water droplet (0.8 Pa) and realize a multisensor system on a chair for sitting posture monitoring.