Journal of the Microelectronics and Packaging Society (마이크로전자및패키징학회지)

The Korean Microelectronics and Packaging Society (한국마이크로전자및패키징학회)
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Prediction of Maximum Bending Strain of a Metal Thin Film on a Flexible Substrate Using Finite Element Analysis

유한요소해석을 통한 유연기판 위의 금속 박막의 최대 굽힘 변형률 예측

  • Jong Hyup Lee (School of Materials Science & Engineering, Research Center for Energy and Clean Technology, Andong National University) ;
  • Young-Cheon Kim (School of Materials Science & Engineering, Research Center for Energy and Clean Technology, Andong National University)
  • 이종협 (안동대학교 신소재공학부 청정에너지소재기술연구센터) ;
  • 김영천 (안동대학교 신소재공학부 청정에너지소재기술연구센터)
  • Received : 2023.12.15
  • Accepted : 2024.03.26
  • Published : 2024.03.30
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Abstract

Electronic products utilizing flexible devices experience harsh mechanical deformations in real-use environments. As a result, researches on the mechanical reliability of these flexible devices have attracted considerable interest among researchers. This study employed previous bending strain models and finite element analysis to predict the maximum bending strain of metal films deposited on flexible substrates. Bending experiments were simulated using finite element analysis with variations in the material and thickness of the thin films, and the substrate thickness. The results were compared with the strains predicted by existing models. The distribution of strain on the surface of film was observed, and the error rate of the existing model was analyzed during bending. Additionally, a modified model was proposed, providing mathematical constants for each case.

유연소자를 이용한 전자제품은 실사용환경에서 가혹한 기계적 변형을 경험한다. 이에 따라 유연소자의 기계적 신뢰성에 대한 연구가 많은 연구자들의 관심을 받고 있다. 본 연구에서는 유연기판에 증착된 금속 박막의 최대 굽힘 변형률을 예측하기 위하여 기존에 사용하는 굽힘 변형률 모델과 유한요소해석을 이용하였다. 박막의 소재 및 두께, 기판의 두께를 달리하여 유한요소해석으로 굽힘 실험을 모사하였고, 기존 모델로 예측된 변형률과 해석결과를 서로 비교하였다. 굽힘 변형 시 박막 첨단과 주위의 변형률 분포를 확인하였고, 굽힘 정도에 따른 기존 모델의 오차율을 정리하였다. 신규수학적 모델을 제시하여 각 경우의 수에 따른 상수를 제시하였다.

Keywords

Acknowledgement

이 연구는 2023년도 정부(산업통상자원부)의 재원으로 한국산업기술진흥원의 지원을 받아 수행된 연구임(P0008458, 2023년 산업혁신인재성장지원사업).

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