A Flexible Piezoelectric Sensor for Microfluidic Applications Using Polyvinylidene Fluoride

A flexible technology for microfluidic applications using piezoelectric polyvinylidene fluoride (PVDF) and polydimethylsiloxane (PDMS) was developed. The flexible piezoelectric PVDF detects the flow rates and impulse pressure signal using piezoelectric characteristics. This study uses microelectromechanical systems (MEMS) technology to fabricate the sensing patterns on PVDF sheets, designs a molding transfer to form the microfluidic channels of the PDMS, and integrates them together. Experimental results show that PVDF films has good piezoelectricity at stretching ratio of 4, the flow rates ranged from 100 to 450 mL/min at dynamic controlling sensing, the miniature curvature radius is about 3 cm, and the cross section of the flexible microchannels is about 200 times 200 mum
²
. The feasibility studies show that molding transfer is an appropriate low-cost technology for fabricating the flexible piezoelectric channels. The PVDF can be easily manufactured using MEMS process because it has a good mechanical strength and electrochemical stability in polymers.