A Patterning Process for Organic Thin Films Using Discharge and Suction Needles

토출 및 흡입 Needle을 이용한 유기 박막 패터닝 공정

  • Kim, Daeyeob (School of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education) ;
  • Shin, Dongkyun (School of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education) ;
  • Lee, Jinyoung (Interdisciplinary Program in Creative Engineering, Korea University of Technology and Education) ;
  • Park, Jongwoon (School of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education)
  • 김대엽 (한국기술교육대학교 전기.전자.통신공학부) ;
  • 신동균 (한국기술교육대학교 전기.전자.통신공학부) ;
  • 이진영 (한국기술교육대학교 창의융합공학협동과정) ;
  • 박종운 (한국기술교육대학교 전기.전자.통신공학부)
  • Received : 2020.03.11
  • Accepted : 2020.03.20
  • Published : 2020.03.31

Abstract

Unlike a printing process, it is difficult to pattern organic thin films in the longitudinal (coating) direction using a coating process. In this paper, we have investigated the feasibility of patterning organic thin films using needles. To this end, we have slot-coated an aqueous poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) solution in the form of a fine stripe or large area and then applied the dual needle; one for discharging the main solvent of the underlying thin film and the other for sucking the dissolved thin film. We have found that the pattern width and depth increase as the moving speed of the plate decreases. However, it is observed that the sidewall slope is very gentle (the length of the slope is of the order of 200 ㎛) due to the fact that the discharged main solvent is widely spread and then isotropic etching occurs. With this scheme, we have also demonstrated that a fine stripe can be obtained by scanning the dual needle closely. To demonstrate its applicability to solution-processable organic light-emitting diodes (OLEDs), we have also fabricated OLED with the patterned PEDOT:PSS stripe and observed the insulation property in the strong light-emitting stripe.

Keywords

Acknowledgement

Supported by : National Research Foundation of Korea (NRF)

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