Electrohydrodynamic Inkjet Printing of OLED Pixel Patterns with High Resolutions

Abstract

We fabricated the OLED devices with high-resolution pixels with the minimum dimension of 5  30 μm by electrohydrodynamic inkjet (e-jet) printing technique combined to the standard micro-fabrication method. An organic small molecule, 2-(t-butyl)-9, 10-bis (20-naphthyl) anthracene (TBADN) was printed as the emitting layer with controlled thicknesses and dimensions. The advantage of e-jet, the possibility of ejection of a jet with nanoscales makes possible to print the solution-based functional material in the smallest pixel which other printing methods are difficult due to their modest printing resolutions. This high-resolution printing capability can resolve the current limitation on reducing pixel dimensions of the vacuum-processed OLED displays, and the low-cost, solution-processibility is advantageous for macroelectronics, including large-area displays.