Piezoelectric DOD (drop-on-demand) ink jet offers a promising combination of high productivity, high reliability and jetting uniformity characteristics (drop volume consistency, velocity characteristics and jet straightness) that are appropriate for jetting organic electronic materials. Because current commercial printheads do not meet the extremely high tolerances necessary for practical manufacturing processes, Spectra is designing a 128 jet printhead specifically for flat panel display (FPD) manufacturing. This paper describes the target specification and technology advancements required for the manufacture of flat panel displays. We will demonstrate the effect of fluid, waveform and head modification on the jetting properties of real polymer OLED (organic light emitting diode) fluids and show that this technology is a viable process for OLED display fabrication. This combination of tailored operating conditions with a purpose-built piezo printhead is proving to be key to meeting the goal of manufacturing high quality FPDs.
Marlene McDonald, Susanne Heun, Neil Tallant, "Advances in Piezoelectric Deposition of Organic Electronic Materials" in Proc. IS&T Int'l Conf. on Digital Printing Technologies (NIP18), 2002, pp 433 - 436, https://doi.org/10.2352/ISSN.2169-4451.2002.18.1.art00003_2