Addressable multi-nozzle electrohydrodynamic jet printing with high consistency by multi-level voltage method

Abstract

It is critical and challenging to achieve the individual jetting ability and high consistency in multi-nozzle electrohydrodynamic jet printing (E-jet printing). We proposed multi-level voltage method (MVM) to implement the addressable E-jet printing using multiple parallel nozzles with high consistency. The fabricated multi-nozzle printhead for MVM consists of three parts: PMMA holder, stainless steel capillaries (27G, outer diameter 400 μm) and FR-4 extractor layer. The key of MVM is to control the maximum meniscus electric field on each nozzle. The individual jetting control can be implemented when the rings under the jetting nozzles are 0 kV and the other rings are 0.5 kV. The onset electric field for each nozzle is ∼3.4 kV/mm by numerical simulation. Furthermore, a series of printing experiments are performed to show the advantage of MVM in printing consistency than the “one-voltage method” and “improved E-jet method”, by combination with finite element analyses. The good dimension consistency (274μm, 276μm, 280μm) and position consistency of the droplet array on the hydrophobic Si substrate verified the enhancements. It shows that MVM is an effective technique to implement the addressable E-jet printing with multiple parallel nozzles in high consistency.

Mechanisms, Capabilities, and Applications of High‐Resolution Electrohydrodynamic Jet Printing

“…[ 84 ] In any such scheme, electrostatic interference between the individual nozzles must be considered, as established from previous studies of electrohydrodynamic ejection of droplets from arrays of large scale nozzles. [85][86][87][88] The small sizes of nozzles associated with high resolution e-jet printing demand a re-consideration of the electrostatics. Experiments indicated that simultaneous printing from 3 different nozzles with inner diameters of 2 µm can be performed with negligible cross-talk effects when the nozzles are separated www.small-journal.com by more than 80 µm.…”

Recent Progress in the Development of Printed Thin‐Film Transistors and Circuits with High‐Resolution Printing Technology

“…This printing technique can be used to produce three‐dimensional structures and high‐resolution patterning, because the small droplets dry very quickly during or immediately after the printing process. Although e‐jet printing typically uses a single nozzle, several studies have developed e‐jet printing that uses multiple nozzles to improve the throughput of the printing technology . The first study of high‐resolution TFTs using e‐jet printing was reported by Rogers and coworkers in 2007 .…”

Large‐Scale Direct‐Writing of Aligned Nanofibers for Flexible Electronics

“…“Auxiliary electrodes,” “Near‐field electrospinning,” “Light‐emitting coaxial nanofibers,” Copyright, respectively, 2003, 2006, 2012, American Chemical Society. “Mathematical model of whipping,” “Silicon based addressable nozzles,” “High consistency by multi‐level voltage,” Copyright, respectively, 2000, 2008, 2015, AIP Publishing. “Rotatable disc collectors,” “Computational model of NFES,” Copyright, 2001, 2010, IOP Publishing.…”

“…Now, the EHD direct‐writing is able to fabricate not only 2D micro/nanopatterns but also 3D frameworks, through either solution or melt‐based electrospinning . When multi‐nozzle is adopted, much more efficient system can be achieved compared to the inkjet printing system . These achievements will no doubt advance the development of EHD direct‐writing in flexible electronics manufacturing.…”