실험 및 유한요소해석에 의한 SU-8 박막의 Tribological 특성 연구

Experimental and Finite Element Study of Tribological Characteristics of SU-8 Thin Film

  • 양우열 (한남대학교 기계공학과) ;
  • 신명근 (한남대학교 기계공학과) ;
  • 김형만 (한남대학교 기계공학과) ;
  • 한상철 (한남대학교 기계공학과) ;
  • 성인하 (한남대학교 기계공학과)
  • 투고 : 2012.07.17
  • 심사 : 2012.12.02
  • 발행 : 2013.04.01


본 연구에서는 SU-8 박막의 마이크로시스템으로의 트라이볼로지적 응용을 목적으로 하여, 원자간 힘 현미경(AFM) 과 콜로이드 프로브를 이용한 실험 및 유한요소해석 기법을 이용하여 SU-8 코팅층의 두께에 따른 트라이볼로지적 특성을 고찰하였다. SU-8 시편은 스핀 코팅기법을 이용하여 두께를 다르게하여 제작하였다. 실험결과 코팅두께가 증가함에 따라 마찰력과 점착력이 감소하여 박막두께에 따른 차이가 존재함을 알 수 있었고, SU-8 표면이 Si 표면에서보다 더 낮은 점착력과 마찰력을 보여주었다. 또한, 시뮬레이션을 통해 두께별로 박막 파손을 유발시키는 임계하중(압력)이 존재하며, 본 연구에서의 200~800 nm 두께범위에서는 1.2~1.8 GPa 로 측정되었다.


연구 과제 주관 기관 : 한국연구재단


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