Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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Improvement of Inverted Hybrid Organic Light-emitting Diodes Properties with Bar-coating Process

바코팅 공정을 이용한 유기 발광 다이오드 특성 향상

  • 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)
  • Received : 2013.04.08
  • Accepted : 2013.05.23
  • Published : 2013.06.01
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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

References

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