Korean Journal of Optics and Photonics (한국광학회지)

Optical Society of Korea (한국광학회)
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Air Gap Measurement between Substrates Using Confocal Technique

공초점 방식을 이용한 기판 사이의 공기갭 측정

  • Lee, Sun-Woo (Department of Electronic Physics, Hankuk University of Foreign Studies) ;
  • Ahn, Kwang-Sin (Department of Electronic Physics, Hankuk University of Foreign Studies) ;
  • Kwon, Nam-Ic (Department of Electronic Physics, Hankuk University of Foreign Studies)
  • 이선우 (한국외국어대학교 전자물리학과) ;
  • 안광신 (한국외국어대학교 전자물리학과) ;
  • 권남익 (한국외국어대학교 전자물리학과)
  • Published : 2009.08.25
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Abstract

A confocal technique was demonstrated for measuring the absolute value of an air gap between substrates. Since the two surfaces were in Rayleigh range of the laser focus for air gaps less than 200 nm, complete interference patterns were observed. And since interference patterns were obtained only from the area of focus, it was an advantage of this method that air gaps between multiple thin films could be measured. Stability is less than 1 nm except in the range where the interference pattern changes slowly.

공초점 방식을 이용하여 두 기판사이의 얇은 공기갭의 두께를 측정하는 방법을 제안하였다. 공기갭이 약 200 nm 이내 일때는 두 기판면이 초점의 레일리 영역 안에 있으므로 완전한 간섭신호를 측정할 수 있었다. 또 초점영역 근처에서의 간섭무늬만 측정되므로 다층 박막중에 존재하는 공기갭이라도 측정할 수 있는 장점이 있다. 간섭무늬 변화가 작은 영역을 제외하면 1 nm 이내의 안정도를 가진다.

Keywords

References

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