2024

Vol.31 No.3

Editorial Office

Review

  • Journal of the Microelectronics and Packaging Society
  • Volume 31(1); 2024
  • Article

Review

Journal of the Microelectronics and Packaging Society 2024;31(1):23-28. Published online: May, 10, 2024

Prediction of Maximum Bending Strain of a Metal Thin Film on a Flexible Substrate Using Finite Element Analysis

  • Jong Hyup Lee and Young-Cheon Kim
    School of Materials Science & Engineering, Research Center for Energy and Clean Technology, Andong National University, 1375, Gyeongdong-ro, Andong-si, Gyeongsangbuk-do 36729, Korea
Corresponding author E-mail: kimyc@anu.ac.kr
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.

Keywords Bending strain, FE analysis, Metal thin film, Flexible substrate

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