Journal of the Microelectronics and Packaging Society (마이크로전자및패키징학회지)

The Korean Microelectronics and Packaging Society (한국마이크로전자및패키징학회)
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Statistical Approach to 3-Dimensional Shape Inspection of Micro Solder Balls

통계적 방법에 의한 마이크로솔더볼의 3차원형상검사

  • Kim, Jee Hong (Department of Display Engineering, Pukyong National University)
  • 김지홍 (부경대학교 융합디스플레이공학과)
  • Received : 2021.11.02
  • Accepted : 2021.11.17
  • Published : 2021.12.30
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Abstract

A statistical approach to inspection of the 3-D shape of micro solder balls is proposed, where an optical method with spatially arranged LED and specular reflection is used. The reflected image captured by a vision system was analyzed to calculate the relative displacements of LED's in the image. Also, the statistics of displacements for the solder balls contained in a captured image are used to detect existing defects, and the usefulness of the proposed method is shown via experiments.

본 논문은 경면반사특성을 갖는 솔더볼의 생산공정 관리와 품질확보를 목적으로 머신비전을 적용한 3차원형상을 결함검사방법으로서, 60미크론 이내의 마이크로 솔더볼을 대상으로 정밀한 위치제어장치가 필요없이 임의로 위치한 솔더볼의 반사영상을 취득 후 통계적으로 분석하여 3차원 형상의 결함유무를 검사하는 방법을 제안한다. 이를 위해 복수개의 LED를 링형태로 배열한 광원을 사용하여 트레이에 위치한 많은 수의 마이크로솔더볼을 동시에 촬영한 영상을 취득하고, 영상처리를 통해 반사되는 LED의 상대적 위치를 구한 후, 통계적 분석을 통하여 결함의 유무를 판단하는 방법을 제안하고 실험을 통해 그 효용성을 보인다.

Keywords

Acknowledgement

이 논문은 부경대학교 자율창의학술연구비(2020년)에 의하여 연구되었음.

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