In this paper, sub-20 nm ferroelectric PVDF–TrFE copolymer nanograss structures with aspect ratios up to 8.9 were developed. This study demonstrated sub-20 nm PVDF–TrFE nanograss structures that are nanoimprinted using a silicon nanograss mold in a single step. Vertically oriented PVDF–TrFE nanopillars were poled using the developed flip-stacking poling method. According to the PFM measurements, the piezoelectricity of flat thin films fabricated in this work reaches 14.0 pm/V. The maximum output voltage of the single PVDF–TrFE nanopillar was 526 mV, and the maximum piezoelectricity of the single PVDF–TrFE nanopillar was 210.4 pm/V. The piezoelectricity of the developed PVDF–TrFE nanograss structures was 5.19 times larger than that of the PVDF–TrFE flat thin films. The developed technique is simple, economical, and easy to fabricate. The developed ferroelectric PVDF–TrFE copolymer nanograss structures, which showed enhanced piezoelectricity compared to the PVDF–TrFE flat thin films, have potential applications in nanotip-based protein biosensors, nanotip-based tactile sensors, and power nanogenerators.

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A new fluidic delivery system for driving fluids on disposable lab-on-a-chip systems using an air-bursting detonator device has been designed, fabricated and successfully characterized in this paper for driving fluid on disposable lab-on-a-chip or point-of-care testing. The disposable air-bursting detonator device uses a pressurized gas source, sealed in a microcavity with a thermoplastic membrane. A microheater positioned on the thermoplastic membrane is used as an electro-thermal heater to melt the sealing membrane thus releasing the pressurized gas to the integrated microfluidic system. The pressurized gas drives liquid samples through designated microfluidic channels. Both air pressure and detonating temperature are adjustable to get the desired driving pressure responses. A 40 mW electrical power pulse applied to the microheater for 700 ms resulted in releasing 650 µJ of stored pneumatic energy in the microcavity and driving a 500 nl sample through the microchannels of an integrated test system. The dynamic pressure response of the fabricated air-bursting detonator has been fully simulated and characterized. Due to its compact structure and fast response, the air-bursting detonator device will be a promising alternative power source to drive fluid samples in disposable lab-on-a-chip systems or portable clinical diagnostic kits.

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