Inkjet Printing of High Aspect Ratio Silver Lines via Laser-Induced Selective Surface Wetting Technique

The field of printed electronics for highly integrated circuits and energy devices demands very fine and highly conductive electric interconnections. In this study, conductive lines having a high cross-sectional aspect ratio were printed via the inkjet printing of Ag nanoparticle inks assisted by a laser-induced selective surface wetting technique: a hydrophobic layer of self-assembled monolayer-treated ZnO nanorods was coated on a glass substrate and selectively ablated by a laser to form micro-channels for the inkjet, whose surface energy changed from 36.3 mJ/m(2) to 51.5 mJ/m(2) before and after the laser irradiation. With the varying width of the laser-ablated channels and pitch of jetted ink drops, the 3D shapes of the printed silver lines were measured to investigate their effects on the widths, heights, and uniformities of the printed patterns. The results showed that the present technique realized a uniform line of 35 mu m width and 0.46 mu m average thickness, having an aspect ratio of 0.013, which is 7.6 times higher than that printed on bare glass.

Automated summary

In this study, conductive lines with high aspect ratio were printed using inkjet printing of Ag nanoparticle inks and laser-induced selective surface wetting technique. The technique involved coating a hydrophobic layer of self-assembled monolayer-treated ZnO nanorods on a glass substrate and selectively ablating it with a laser to create micro-channels for inkjet printing. By adjusting the width of the laser-ablated channels and pitch of the ink drops, the 3D shape of the printed silver lines was measured to study their effects on width, height, and uniformity. The results showed that the technique achieved uniform lines with a width of 35 µm and an average thickness of 0.46 µm, with an aspect ratio 7.6 times higher than that of lines printed on bare glass.