Precise Electrohydrodynamic Direct-Write Micro-Droplets Based on a Designed Sinusoidal High-Voltage AC Power

Abstract

The precise manufacturing of micro/nano structures is the key to the rapid development of flexible micro/nano systems. In this paper, a sinusoidal high-voltage alternating current (AC) power is designed for electrohydrodynamic direct-writing (EDW) technology. A push-pull converting circuit is utilized as the direct current (DC) voltage regulator power of a full-bridge inverter circuit. A single-phase full-bridge inverter circuit is used to output the controllable AC voltage, which is then boost-filtered to output the high-voltage sinusoidal AC signal. The amplitude of the output sinusoidal voltage is proportional to the input voltage and the modulation degree of the sinusoidal pulse width modulation (SPWM) inverter circuit. Then, the designed sinusoidal high-voltage AC power is used in the AC EDW process to print micro-droplets. The deposition frequency and the average diameter of droplets can be effectively controlled by adjusting the voltage amplitude and the voltage frequency. The design of this sinusoidal high-voltage AC power will promote research on the applications of EDW technology in the field of micro/nano manufacturing.

Fast on–off controlling of electrohydrodynamic printing based on AC oscillation induced voltage

“…In the initial stage of applying the pulse voltage, the instability caused by large impulse voltage will lead to intense oscillation of the suspended droplets at the nozzle, and the jet will take away a larger volume of solution, which means the uniformity of droplets may be negatively affected [26][27][28] . In the previous works of our group, it has been proved that the use of AC power could more effectively suppress the negative effects of charge accumulation, and the sharp edge of the voltage wave is likely to cause instability in the early stages of ejection process 29,30 .…”