Drop-on-Demand Direct Printing of Colloidal Copper Nanoparticles by Electrohydrodynamic Atomization

Abstract

Electrohydrodynamic inkjet printing technology has recently become attractive in many industrial fabrication fields mainly due to its advantage of smaller drop generation as compared to the diameter of the delivery nozzle. In this article, drop-on-demand (DoD) printing of colloidal solution containing copper nanoparticles through electrohydrodynamic atomization (EHDA) is investigated. By applying a novel forward multistep waveform (FMSW) superimposed on dc biased voltage, charged fluid drops containing copper nanoparticles are deposited on glass substrate. The main focus of this study is to generate uniform droplets of conductive copper ink in a controlled fashion by varying amplitude and frequency of the applied waveform. The deposited patterns show a series of uniform-sized drops with regular spacing. Using this DoD printing technique, it is feasible to print a variety of patterns of dots and conductive continuous or discontinuous lines.

Keywords:

• Atomization
• Copper
• Drop-on-Demand
• Electrohydrodynamic
• Forward-multi-step
• Frequency
• Hydrophilic
• Inkjet
• Nanoparticles
• Printing
• Relaxation-time

ACKNOWLEDGMENT

This study was supported by the Ministry of Knowledge Economy, South Korea, through the “Strategy Technology Development Project.”