Fujifilm and imec have demonstrated full-color organic light-emitting diodes (OLED) by using their jointly-developed photoresist technology for organic semiconductors, a technology that enables submicron patterning. This breakthrough result paves the way to producing high-resolution and large organic Electroluminescent (EL) displays and establishing cost-competitive manufacturing methods. Organic EL displays are increasingly used for televisions, mobile devices including smartphones as well as wearable devices. Today’s products require organic EL displays of high pixel density, i.e. around 200ppi for 4K televisions, 500ppi for full HD mobile devices and even higher density for compact displays for wearable devices. There has been active R&D for organic semiconductors to develop a high-resolution patterning method for organic EL materials to be used in these products.
In the latest achievement, Fujifilm and imec produced full-color OLEDs with the photoresist technology for organic semiconductors and successfully verified their performance. Red, green and blue organic EL materials were patterned, each in the subpixel pitch of 20μm, to create full-color OLEDs. An OLED array of 40 x 40 dots at the resolution of 640ppi was realized and illuminated with UV rays to confirm that red, green and blue dots separately emitted light. The emission of red, green and blue lights was also confirmed in a test involving the application of voltage rather than illumination, confirming its correct performance.