Multiple Nozzle Electrohydrodynamic Jet Printing

Printing approaches used in the graphic arts, especially ink-jet printing, have recently become of interest for high-resolution manufacturing applications in electronics, biotechnology, and microelectromechanical systems. The resolution of ink-jet techniques unfortunately is typically ~20 – 30 μm in best case scenarios [1]. Electrohydrodynamic jet (e-jet) printing is an attractive alternative to ink-jet printing as a nanomanufacturing platform. While ink-jet printing typically results in final printed spot sizes with diameters comparable to the nozzle from which they were ejected, e-jet allows for much smaller sized printed droplets (< 1 μm), a result of electrostatically induced focusing that takes place at the tip of the ink meniscus prior to deposition [2].

While promising in concept, robust e-jet printing systems are still in their infancy. E-jet has typically been performed using single capillaries or needles as the fluid carrier [2,3]. In this presentation, we will demonstrate an integrated printing toolbit, consisting of an array of three individually addressable e-jet nozzles microfabricated in a silicon wafer, integrated with a microfluidic layer for the delivery of ink to each separate nozzle. The integration of a microfluidic network and an array of individually addressable nozzles with current e-jet technology will eventually allow for the simultaneous deposition of multiple ink types on a single substrate with spot sizes in the submicron regime.

[1] Parashkov, R., Becker, E., Riedl, T., Johannes, H. H., Kowalsky, W., Proceedings of the IEEE, "Large area electronics using printing, methods," 2005, 93, 1321-1329.

[2] Park, J.-U., Hardy, M. T., Kang, S., Barton, K. L., Adair, K. G., Mukhopadhyay, D., Lee, C., Strano, M. S., Alleyene, A. G., Georgiadis, J. G., Ferreira, P., M., Rogers, J. A., Nature Materials, "High Resolution Electrohydrodynamic Jet Printing With Application Examples in Printed Electronics," 2007, 6, 782-789.

[3] Park, J.-U., Lee, J. H., Paik, U., Lu, Y., Rogers, J. A., Nano Letters, “Nanoscale Patterns of Oligonucleotides Formed by Electrohydrodynamic Jet Printing with Applications in Biosensing and Nanomaterials Assembly,” 2008, 8, 4210-4216.