Journal of the Semiconductor & Display Technology (반도체디스플레이기술학회지)

The Korean Society Of Semiconductor & Display Technology (한국반도체디스플레이기술학회)
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Study on Fluid Distribution in Slot-die Head Using CFD

CFD를 이용한 슬롯 다이 헤드 내부의 유체 분포 분석

  • Yoo, Suho (School of Electrical, Electronic & Communication Engineering, Korea University of Technology and Education) ;
  • Kim, Gieun (School of Electrical, Electronic & Communication Engineering, Korea University of Technology and Education) ;
  • Shin, Youngkyun (School of Electrical, Electronic & Communication Engineering, Korea University of Technology and Education) ;
  • Park, Jongwoon (School of Electrical, Electronic & Communication Engineering, Korea University of Technology and Education)
  • 유수호 (한국기술교육대학교 전기.전자.통신공학부) ;
  • 김기은 (한국기술교육대학교 전기.전자.통신공학부) ;
  • 신영균 (한국기술교육대학교 전기.전자.통신공학부) ;
  • 박종운 (한국기술교육대학교 전기.전자.통신공학부)
  • Received : 2022.11.02
  • Accepted : 2022.12.12
  • Published : 2022.12.31
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Abstract

Using a CFD (computational fluid dynamics) simulation tool, we have offered a design guideline of a slot-die head having a simple T-shaped cavity through an analysis of the fluid dynamics in terms of cavity pressure and outlet velocity, which affect the uniformity of coated thin films. We have visualized the fluid flow with a transparent slot-die head where poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) is injected. We have shown that the fluid dynamics inside the slot-die head depends sensitively on the cavity depth, cavity length, land length, and channel gap (i.e., shim thickness). Of those, the channel gap is the most critical parameter that determines the uniformity of the pressure and velocity distributions. A pressure drop inside the cavity is shown to be reduced with decreasing shim thickness. To quantify it, we have also calculated the coefficient of variation (CV). In accordance with Hagen-Poiseuille's laws and electron-hydraulic analogy, the CV value is decreased with increasing cavity depth, cavity length, and land length.

Keywords

Acknowledgement

이 논문은 2022년도 한국기술교육대학교 교수 교육연구진흥과제 지원에 의하여 연구되었음.

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