Design, Fabrication, and Characterization of Linear Multiplexed Electrospray Atomizers Micro-Machined from Metal and Polymers

Abstract

Multiplexed electrospray is a promising aerosol generation technique to produce high throughput quasi-monodisperse droplets in the nanometer and micron size range. Here we report the design, fabrication, analysis, and performance of a linear electrospray (LINES) system. The fabrication of the nozzle array is based on a precision computer numerical control (CNC) micromachining platform with 1-micron resolution. This rapid prototyping approach offers the flexibility of creating devices from a wide range of materials including metals and polymers with packing densities on par with silicon microfabrication at 20 sources/cm for LINES devices and 460 sources/cm2 for the two-dimensional array. The LINES device uses a slot extractor design to simplify alignment and enhance operation robustness. We also used dummy nozzles (posts without fluidic channels) to offset edge effect on electric field and improved droplet size uniformity. We derived the approximate spray expansion model from charge conservation and Gauss’...