P‐73: High‐Resolution Color Patterning of an OLED Device via Capillary‐Induced Ink Filling and a Sublimation Transfer Process

Abstract

We studied capillary‐induced ink transfer technology in order to achieve a breakthrough in relation to the fabrication of a high‐resolution color patterning for OLED display. In this approach, the selective surface treatment of a donor substrate, capillary‐induced ink filling, and a solidified ink sublimation transfer technique are important processes. We investigated the characteristics of ink as it was filled into microchannels and the sublimation transfer characteristics of EML films in accordance with the volume fraction of 1,2‐dichlorobenznene (oDCB) (oDCB/T) and the spin speeds. Through a selective surface treatment, red EML ink was successfully deposited into the microchannels using a conventional spin‐coating process. With the optimized ink filling properties and the sublimation transfer process, we fabricated phosphorescent OLED devices with striped EML patterns. Finally, we demonstrated that a red EML layer can be patterned with a width of 14 µm and pitch of 36.1 µm (700 ppi).