2024

Vol.31 No.2

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  • Journal of the Microelectronics and Packaging Society
  • Volume 30(4); 2023
  • Article

Review

Journal of the Microelectronics and Packaging Society 2023;30(4):105-111. Published online: Feb, 20, 2024

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DOI : doi.org/10.6117/kmeps.2023.30.4.0105

Reliability of Cu Interconnect under Compressive Fatigue Deformation Varying Interfacial Adhesion Treatment

  • Min Ju Kim, Jeong A Heo, Jun Hyeok Hyun, and So-Yeon Lee†
    Department of Materials Science and Engineering, Kumoh National Institute of Technology, Gumi, Gyeongbuk 39177, Korea
Corresponding author E-mail: soyeonlee@kumoh.ac.kr
Abstract

Electronic devices have been evolved to be mechanically flexible that can be endured repetitive deformation. This evolution emphasizes the importance of long-term reliability in metal wiring connecting electronic components, especially under bending fatigue in compressed environments. This study investigated methods to enhance adhesion between copper (Cu) and polyimide (PI) substrates, aiming to improve the reliability of copper wiring under such conditions. We applied oxygen plasma treatment and introduced a chromium (Cr) adhesion layer to the polyimide substrate. Our findings revealed that these adhesion enhancement methods significantly affect compression fatigue behavior. Notably, the chromium adhesion layer, while showing weaker fatigue characteristics at 1.5% strain, demonstrated superior performance at 2.0% strain with no delamination, outperforming other methods. These results offer valuable insights for improving the reliability of flexible electronic devices, including reducing crack occurrence and enhancing fatigue resistance in their typical usage environments.

Keywords Flexible device, Reliability, Interface adhesion, Metal film, Polyimide

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