Donggeon Han1 Yasser Khan1 Karthik Gopalan1 Ana Arias1

1, University of California at Berkeley, Berkeley, California, United States

Current innovations in displays and sensors require light sources with a tunable shape of light emission. Organic light-emitting diodes (OLEDs) provide a large degree of freedom in designing the light emission, as the shape of the light emission is defined by the active area of the OLEDs. Conventionally, pattering the active area involves procedures that use subtractive methods, such as photolithography or etching. Here, we show multiple ways to pattern the emission area of the OLEDs with printing techniques. A number of printing schemes such as stencil printing, spray coating, and screen printing are studied and utilized. We use spray coating and screen printing to deposit dielectric layers with desired patterns. At a luminance of 1000 cd/m2, the OLEDs with circular emissive areas demonstrate current density of 7.8 and 11 mA/cm2, EQE of 2.4 and 2.2 %, and luminous efficacy of 6.3 and 5.3 lm/W, respectively for spray-coated and screen-printed pattered dielectrics. The dielectric patterning methods presented here can be used to fabricate OLEDs with varied shapes of light emission, enabling novel displays and sensors.