Flexible, highly sensitive and reliable piezocapacitive pressure sensor with honeycomb-like microarchitecture fabricated using filament-processed mold

Abstract

Highly sensitive flexible pressure sensors have been extensively studied due to their promising applications in many fields. Various sensing mechanisms have been proposed to convert pressure into a readable electrical signal, among which piezocapacitive presents advantages due to its simple structure and convenient integration. The modification of the dielectric layer composing these sensors is a common strategy to improve their sensing performance. In this paper, we propose the fabrication of a novel capacitive-based flexible pressure sensor with honeycomb-like microarchitecture by using femtosecond laser filament based far-field technique. The fabricated flexible sensing device is assembled face-to-face with two layers of micro-structured polydimethylsiloxane thin films that is duplicated from laser filament-processed silicon mold. The as-prepared flexible sensor features excellent sensing performance with high reliability, and enables detection of multi-modal signals, including pressure, proximity, and bending. Owing to the advantages mentioned above, the obtained flexible pressure sensor can be attached on non-planar human skin to monitor the physiological signals as well as joint deformation during exercise, revealing it great application potential in cutting-edge fields, such as robotic tactility.