Journal of the Semiconductor & Display Technology (반도체디스플레이기술학회지)

The Korean Society Of Semiconductor & Display Technology (한국반도체디스플레이기술학회)
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Simulation of Capillary Phenomenon for Solution Coating of High-uniformity Organic thin Films

고균일 유기박막 코팅을 위한 모세관 현상 전산모사

  • 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)
  • 신동균 (한국기술교육대학교 창의융합공학협동과정) ;
  • 홍기영 (한국기술교육대학교 전기.전자.통신공학부) ;
  • 박종운 (한국기술교육대학교 전기.전자.통신공학부) ;
  • 서화일 (한국기술교육대학교 전기.전자.통신공학부)
  • Received : 2017.03.20
  • Accepted : 2017.03.25
  • Published : 2017.03.31
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Abstract

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 $40^{\circ}$.

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References

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