A Wafer Pre-Alignment System Using One Image of a Whole Wafer

하나의 웨이퍼 전체 영상을 이용한 웨이퍼 Pre-Alignment 시스템

  • Koo, Ja-Myoung (Dept. of Electrical and Electronics Engineering, Korea University of Technology and Education) ;
  • Cho, Tai-Hoon (School of Computer Engineering, Korea University of Technology and Education)
  • 구자명 (한국기술교육대학교 전기전자공학과) ;
  • 조태훈 (한국기술교육대학교 컴퓨터공학부)
  • Received : 2010.08.23
  • Accepted : 2010.09.15
  • Published : 2010.09.30

Abstract

This paper presents a wafer pre-alignment system which is improved using the image of the entire wafer area. In the previous method, image acquisition for wafer takes about 80% of total pre-alignment time. The proposed system uses only one image of entire wafer area via a high-resolution CMOS camera, and so image acquisition accounts for nearly 1% of total process time. The larger FOV(field of view) to use the image of the entire wafer area worsen camera lens distortion. A camera calibration using high order polynomials is used for accurate lens distortion correction. And template matching is used to find a correct notch's position. The performance of the proposed system was demonstrated by experiments of wafer center alignment and notch alignment.

Keywords

References

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