Numerical simulation of coaxial electrohydrodynamic jet and printing nanoscale structures.

The aim of this work is to simulate the formation of coaxial electrohydrodynamic jet (CE-Jet) and obtain the optimized working parameters for coaxial electrohydrodynamic focused jet printing (CEFJP), then further direct writing nanoscale structures. In this paper, a pioneering simulation of CE-Jet process based on three phase flow of liquid–liquid–air model was developed. The photoresist (AZ703)/silicone oil was employed to verify the simulation. The simulated result of the CE-Jet consisted with the experimental result very well, which proves the correction of the CE-Jet model. Based on the simulation, the effect of working parameters including the applied voltage and the flow rate of inner coaxial liquid on the morphology and size of the CE-Jet were examined. With the use of the optimized working parameters obtained from the simulation and taking the materials of lead zirconate titanate (PZT) and photoresist (AZ703) as inner liquid, the stable nanoscale inner jet was focused by the compound effect of electrical shearing force, viscous shearing force and internal pressure. Then, the nanostructures of various patterns with diameter of 70 nm were directly printed. The CE-Jet model developed in this work provides a powerful tool to investigate the CEFJP process, and the CEFJP technique exhibited a promising method for producing nanoscale structures for M/NEMS devices. [ABSTRACT FROM AUTHOR]