Design and fabrication of piezoelectric microactuators based on β-poly(vinylidene fluoride) films for microfluidic applications

Abstract

This paper reports a fabrication method for producing piezoelectric poly(vinylidene fluoride) films in their electroactive β-phase that features controlled thickness, smooth and flat surface, and high transparency. These piezoelectric films are suitable for being used as integrated microactuators, such as piezoelectric pumps and/or mixers, in microfluidic applications. Their actuation circuit design is also reported. ATR-FTIR, UV-VIS transmittance spectroscopy and SEM techniques were used for calculating the β-phase content, for determining the transparency and for evaluating the morphology of the produced β-PVDF films, respectively. β-PVDF films with a thickness of about 25 μm were deposited by spin-coating. It was concluded that the processing parameter that mostly affect the films quality was their drying temperature. Indeed, the drying temperature of 30 ºC proved to be the most suitable for obtaining non-porous and transparent films, with a β-phase content of approximately 75%.