Hybrid capacitive/piezoelectric visualized meteorological sensor based on in-situ polarized PVDF-TrFE films on TFT arrays

Abstract

A novel type of hybrid capacitive/piezoelectric sensor was designed and fabricated for real-time monitoring of the size, rate, and frequency of rainfall. The design is based on in situ polarized poly (vinylidene fluoride–trifluoroethylene) (PVDF-TrFE) films on thin-film transistor (TFT) arrays. The polarization of the PVDF-TrFE film with an area of 200 × 200 mm2 can be achieved within 5 min using an in-situ polarization process, and the piezoelectric coefficient d33 can reach an average value of 27 pC/N with a uniform distribution across the area. The PVDF-TrFE piezoelectric sensor exhibits high sensitivity, with a raindrop frequency error margin of 1%. The capacitive sensor is composed of the PVDF-TrFE films and TFT arrays, which can be used to determine the size and shape of raindrops on the sensor surface. In addition, the sensor can also be used for high-precision detection of water level, with a resolution of 50 μm.