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http://dx.doi.org/10.7736/KSPE.2013.30.6.589

Improvement of Inverted Hybrid Organic Light-emitting Diodes Properties with Bar-coating Process  

Kwak, Sun-Woo (Department of Printed Electronics, Korea Institute of Machinery and Materials)
Yu, Jong-Su (Department of Printed Electronics, Korea Institute of Machinery and Materials)
Han, Hyun-Suk (Department of Printed Electronics, Korea Institute of Machinery and Materials)
Kim, Jung-Su (Research & Development Team, Printed Electronics Mechanical System)
Lee, Taik-Min (Department of Printed Electronics, Korea Institute of Machinery and Materials)
Kim, Inyoung (Department of Printed Electronics, Korea Institute of Machinery and Materials)
Publication Information
Journal of the Korean Society for Precision Engineering / v.30, no.6, 2013 , pp. 589-595 More about this Journal
Abstract
Solution processed conjugated molecules enable to manufacture various electronic devices by unconventional and cost effective patterning methods as screen or gravure printing. Spin-coating is the most popularly used method to form conjugated polymeric film for various electronic devices. The coating method has certain disadvantages such as a large amount of unwanted wastes, difficulty forming a film with a large area, and impossible to apply roll-to-roll manufacturing. We present here a promising alternative coating method, bar-coating for conjugated polymer film and OLED with the bar coated light emitting layer. In this papers, we show atomic force microscope images of spin- and bar-coated Poly[(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-(benzo[2,1,3]thiadiazol-4,8-diyl)] (F8BT) films on substrate. The bar-coated film showed a slight lower RMS roughness (1.058 [nm]) than spin-coated film (1.767 [nm]). It means the bar-coating is suitable method to form light emitting layers in OLEDs. By using bar-coating process, an OLED obtained with 4.7 [cd/A] in maximum current efficiency.
Keywords
Bar-coating process; OLEDs; PLEDs; Inverted structure; Printed electronics;
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