An Analysis of Screen Printing using Solder Paste

솔더 페이스트를 이용한 스크린 프린팅 공정 해석

  • Seo, Won-Sang (Graduate School of NID Fusion Tech., Seoul National Univ. of Tech.) ;
  • Min, Byung-Wook (Graduate School of NID Fusion Tech., Seoul National Univ. of Tech.) ;
  • Kim, Jong-Ho (Dept. of Product Design and Manufac. Eng., Seoul National Univ. of Tech.) ;
  • Lee, Nak-Kyu (Dept. of Manufac. Convergence Tech., Korea Institute of Industrial Tech.) ;
  • Kim, Jong-Bong (Dept. of Automotive Eng., Seoul National Univ. of Tech.)
  • 서원상 (서울산업대학교 NID 융합기술대학원) ;
  • 민병욱 (서울산업대학교 NID 융합기술대학원) ;
  • 김종호 (서울산업대학교 제품설계금형공학과) ;
  • 이낙규 (한국생산기술연구원 융합생산기술연구부) ;
  • 김종봉 (서울산업대학교 자동차공학과)
  • Received : 2010.01.15
  • Accepted : 2010.03.24
  • Published : 2010.03.30

Abstract

In this study, analyses on the stencil printing using solder paste were carried out. The key design parameters in the stencil printing process are printing conditions, stencil design, and solder paste properties. Among these parameters, the effects of physical properties of solder paste such as viscosity, surface tension, and contact angle on the stencil printing process were investigated. The analyses were performed for simple geometry and boundary conditions. In the analysis, solder paste was pushed into a stencil hole by pressure instead of printer pad. Considering the geometry and computational efficiency, axisymmetric analyses were adopted. A commercial software (COMSOL), which is well known in the area of micro-fluids analysis, was used. From the results, it was shown that viscosity of solder paste had an effect on the filling speed, while surface tension and contact angle had an effect on the filling shape.

본 연구에서는 솔더 페이스트를 이용한 프린팅 공정의 해석에 대해 연구를 수행하였다. 스텐실 프린팅 공정의 설계에서 중요한 인자는 프린팅 조건, 스텐실 설계, 그리고 솔더 페이스트의 물성 등이다. 본 연구에서는 이 인자들 중에서, 솔더 페이스트의 점도와 표면장력, 그리고 솔더 페이스트와 스텐실 사이의 접촉각이 프린팅 공정의 성능에 미치는 영향을 해석을 통해 파악하였다. 실제 해석에 앞서 압력에 의해서 솔더 페이스트가 스텐실에 채워지는 단순화된 형상과 조건으로 해석을 수행하였다. 해석은 마이크로 유동의 해석에 많이 이용이 되고 있는 상용 소프트웨어인 콤솔(COMSOL)을 이용하였고 축대칭으로 해석하였다. 해석 결과, 솔더 페이스트의 점도는 충진률에 큰 영향을 줌을 알 수 있었고 표면장력과 접촉각은 충진되는 형상에 영향을 줌을 알 수 있었다.

Keywords

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