Jeong-Beom Ko

Development of Pneumatic Ink Supply System for Electrostatic head on Meniscus control

The Electrostatic Inkjet system has many applications in cost and time effective manufacturing of printed electronics like RFIDs, OLEDs and flexible displays etc. This paper presents pneumatic ink supply system for an electrohydrodynamic deposition (EHD) setup for the precise pressure control to produce a small amount of discharge at the end of the capillary. The meniscus shape depends upon the applied pneumatic pressure to the ink supply system. Furthermore, this paper also compares meniscus shapes at different applied pneumatic pressures. It is concluded that patterning of constant line-width can be achieved better by controlling the meniscus shape using this technique.

Development of hybrid SAW-ED system for conductive thin-layer

In the hybrid SAW-ED deposition system for conductive thin-layer, droplets generation depend upon the SAW. Also, the electrostatic field can help pull off the droplets to the substrates. In this paper, the efficiency of hybrid SAW-ED head is studied analytically. For the development of hybrid SAW-ED deposition system, the optimized parameters for conductive thin-layer can be ascertained from the results discussed here. The background of this research is to get micro droplets and successive spray and the optimal conditions for the development of conductive thin-layer needed for devices of printed electronics through hybrid SAW-ED deposition system.

Effect of different ground hole size on stable meniscus in electrostatic integrated deposition inkjet head

There have been growing interests in direct patterning of metallic contents on the surface of the substrate without including complex steps of the micro fabrication lithography process. The direct fabrication process using ink-jet printing can be expected to be a powerful tool for both nanotechnology research and applications such as micro electronics. The electrostatic inkjet system has a huge number of applications in terms of cost and time effected manufacturing of printed electronics like RFID, electronic devices and flexible display, solar cell, sensors etc. Inkjet printers operate by propelling various size droplets of conductive ink onto the non conductive substrate. For experimental purpose, an integrated electrostatic inkjet nozzle head was fabricated. For the charging of ink meniscus, an electrode is inserted inside the nozzle head containing conductive ink. The difference between the charge meniscus and ground electrode is depended on the ink properties like surface tension, viscosity and number of metallic pigments. Therefore, for the extraction of droplets, a ring type ground terminal with internal diameter of 1.5mm, 1mm. 0.5mm with a fixed distance of 500um from the meniscus is employed. The paper is focused on the different meniscus shape and extractions in meniscus before dripping is evaluated through experiments. And optimal ground is proposed. This study will help to develop and analysis the integrated electrostatic nozzle head and aspects of the nozzle head.