고균일 유기박막 코팅을 위한 모세관 현상 전산모사

Simulation of Capillary Phenomenon for Solution Coating of High-uniformity Organic thin Films

  • 신동균 (한국기술교육대학교 창의융합공학협동과정) ;
  • 홍기영 (한국기술교육대학교 전기.전자.통신공학부) ;
  • 박종운 (한국기술교육대학교 전기.전자.통신공학부) ;
  • 서화일 (한국기술교육대학교 전기.전자.통신공학부)
  • Shin, Dong-Kyun (Interdisciplinary Program in Creative Engineering, Korea University of Technology and Education) ;
  • Hong, Gi-Young (School of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education) ;
  • Park, Jong-Woon (School of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education) ;
  • Seo, Hwa-Il (School of Electrical & Electronic & Communication Engineering, Korea University of Technology and Education)
  • 투고 : 2017.03.20
  • 심사 : 2017.03.25
  • 발행 : 2017.03.31

초록

When a substrate with a pixel-defining layer (bank) is coated, there arises capillary force due to surface tension and adhesive forces between a solvent and the bank layer. It brings in a degradation of film thickness and emission uniformities within pixels. With an attempt to suppress it, we have performed fluid flow simulations of capillary arise by varying the contact angle of bank and the bank structure. We have first demonstrated that the fluid flow model can reproduce the capillary phenomenon that was observed experimentally. It has been found that capillary arise can be suppressed using a hydrophobic material for the bank layer. Furthermore, it was suppressed by tilting the sidewalls outwardly (i.e., using a positive photoresistor). We can obtain very uniform films when the slope is $50^{\circ}$ with the contact angle of $40^{\circ}$.

키워드

참고문헌

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