Fabrication of nanoscale nozzle for electrohydrodynamic (EHD) inkjet head and high precision patterning by drop-on-demand operation.

: Electrohydrodynamic (EHD) spraying has been utilized in applications varying from micro-colloid thrusters to technology for film deposition and inkjet printing. Recently, EHD inkjet heads were developed to facilitate the fabrication of printed electronics such as digital displays, printed circuit boards (PCBs), and solar cells. Here, we report the fabrication and application of nanoscale nozzles for EHD inkjet printing. The nozzles were fabricated by depositing an electrically conductive layer on either the inside or outside of quartz micropipettes with sub-micron diameter tips. With the drop-on-demand control needed for inkjet heads, our nanoscale nozzles dispensed silver droplets in fine patterns on glass substrates.