Top-Emission Organic Light-Emitting Diodes with Ink-Jet Printed Self-Aligned Emission Zones

We have investigated a method of fabricating ink-jet printed self-aligned emission zones for top-emission organic light-emitting diodes. To obtain a bright emission, the number of ink-jet printed shots was varied. From the viewpoint of surface roughness of the bottom electrode, AlNd was used. To reduce sputtering damage, a buffer layer with the hole transport ability of MoO3 was also employed. As a result, the maximum luminance obtained was 1,000 cd/m2. By application of this fabrication technique, we have achieved a printed display panel 30×30 mm2 resolution of 300 pixels per inch.