Abstract
Poor dry-film uniformity from wet-processed organic light emitting diode (OLED) because of the coffee-ring effect was improved in this work by compensating the first inkjet-printed poly (3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) with a second inkjet-printed one. Compensation volume, drop arrangement, and printing sequence were studied for optimized and improved film uniformity. In addition, a uniformity evaluation method was proposed in this work by image operation to quantify and qualify the OLED dry-film morphology for the first time.