Design and evaluation of a linear nozzle array with double auxiliary electrodes for restraining cross-talk effect in parallel electrohydrodynamic jet printing

Abstract

It is attractive and challenging to fabricate micro-nano scale patterns in large area by parallel electrohydrodynamic jet printing (E-jet printing) with nozzle array. However, cross-talk effect (i.e. interference phenomenon) between nozzles may probably lead to poor positioning accuracy and cause jet instability. In this paper, design and evaluation of a special linear nozzle array with double auxiliary electrodes at both ends were proposed to restrain the cross-talk effect. Firstly, the numerical simulation model of multi-nozzle E-jet printing was established considering with electro-hydraulic coupling effect. The corresponding multi-nozzle E-jet printing processes in several geometry configurations were successfully simulated based on a commercial multi-physical software ‘COMSOL’. Secondly, the unique design of new type linear nozzle array with double auxiliary electrodes was proposed after accomplishing theoretical analysis and comparison study of simulation results. Thirdly, several experiments were carried out on a constructed multi-nozzle E-jet printing system to verify feasibility and effectiveness of the provided design. The experiments show that the proposed manner has obvious advantages in restraining cross-talk compared with traditional suppressing method ‘with single flat-head auxiliary electrode at both ends’. When nozzle space is 0.5 mm, the jet deflection angle 2.8° and Taylor cone angle 3.3° could be reduced to 0° and 0.05° with two methods respectively. Finally, the printability of fabricated new multi-nozzle was also characterized. Microscale droplets array (mean diameter about 200–240 μm) could be achieved with no deflection and the gap between them is equal with the distance between adjacent nozzles. This study can provide a reference for the design of high integrated printhead and E-jet printing system.