Piezoelectric Acoustic Vibration Sensor Based on Flexible-PCB Spin-coated with PVDF-TrFE

This work presents a cantilever-structured acoustic sensor made on a flexible PCB substrate using PVDF-TrFE polymer sandwiched between two metals. On a flexible PCB, an electroplated copper metal base layer was spin-coated with a piezoelectric PVDF-TrFE polymer solution, and a silver top electrode was sputtered as a top electrode on the polymer. The vibration sensor based on flexible PCB was laser-cut in a cantilever with dimensions 5 x 2 mm. The sensor was tested under the influence of sinusoidal acoustic sound frequencies from 600– 1200 Hz. The spin-coated piezoelectric materials show responsiveness when detecting changes in sound frequencies without the need for poling or the use of polar solvents.