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Analytic and Numerical Study for air Bubble Defect of UV-NIL Process

UV-NIL 공정의 기포 결함에 대한 해석적 및 수치적 연구

  • 석정민 (서울대학교 기계항공공학부) ;
  • 김남웅 (동양미래대학교 기계공학부)
  • Received : 2012.04.24
  • Accepted : 2012.06.05
  • Published : 2012.06.15

Abstract

In this paper, the air bubble formation mechanism in the rectangular and triangular line-and-space pattern during dispensing UV Nanoimprint Lithography (UV-NIL) at an atmospheric condition is studied. To investigate the air bubble formation, an analytic model based on geometric approach and a numerical model based on CFD(computational fluid dynamics) were used in the analysis. It was found in the numerical analysis that every time the flow front passed through a corner of the pattern, it proceeded with a newly formed shape, occurring due to interface reconfiguration, since the flow fronts were formed such that they minimized the surface energy. Moreover, the conditions for the air bubble formation were investigated by applying the analytic analysis based on geometric approach and the numerical analysis. Good overall agreement was found between the analytic and numerical analysis.

Keywords

References

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