마이크로전자및패키징학회지 (Journal of the Microelectronics and Packaging Society)

  • 제30권4호
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  • Pages.105-111
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  • 2023
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  • 1226-9360(pISSN)
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  • 2287-7525(eISSN)
한국마이크로전자및패키징학회 (The Korean Microelectronics and Packaging Society)
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유연소자용 기판과의 접착 특성에 따른 구리 배선의 압축 피로 거동 및 신뢰성

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

  • 김민주 (금오공과대학교 신소재공학부) ;
  • 현준혁 (금오공과대학교 신소재공학부) ;
  • 허정아 (금오공과대학교 신소재공학부) ;
  • 이소연 (금오공과대학교 신소재공학부)
  • Min Ju Kim (Department of Materials Science and Engineering, Kumoh National Institute of Technology) ;
  • Jeong A Heo (Department of Materials Science and Engineering, Kumoh National Institute of Technology) ;
  • Jun Hyeok Hyun (Department of Materials Science and Engineering, Kumoh National Institute of Technology) ;
  • So-Yeon Lee (Department of Materials Science and Engineering, Kumoh National Institute of Technology)
  • 투고 : 2023.12.22
  • 심사 : 2023.12.30
  • 발행 : 2023.12.30
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초록

차세대 전자기기는 기계적인 굽힘이나 말림(rolling) 변형이 반복적으로 가능한 형태로 발전하고 있다. 이에 따라 전자기기 내부 소자들 간의 연결을 위한 금속 배선의 기계적인 신뢰성 확보가 필수적이며, 특히, 실제 사용 환경을 모사한 압축 환경에서의 굽힘 피로 변형에 대한 신뢰성 평가가 중요하다. 본 연구에서는 구리(Cu)와 폴리이미드(Polyimide, PI) 기판 간의 접착력을 향상시키고, 굽힘 피로 변형 환경에서 구리 배선의 신뢰성을 높이기 위한 방법을 탐구했다. 접착력 향상을 위해 폴리이미드 기판에 산소 플라즈마 처리와 크롬(Cr) 접착층 도입이라는 두 가지 방법을 적용하고, 이들이 압축 상황에서의 피로 거동에 미치는 영향을 비교 분석했다. 연구 결과, 접착력 향상 방법에 따라 압축 피로 거동에서 차이가 발생하는 것을 확인했다. 특히, 크롬 접착층을 도입한 경우 1.5% 변형률에서는 크랙 생성이 주된 변형 메커니즘이며, 피로 특성이 취약한 결과를 얻었으나, 2.0%의 높은 변형률에서는 플라즈마 처리법에 비해 박리가 발생하지 않아 가장 개선된 피로 특성을 나타냈다. 본 연구의 결과는 유연 전자기기의 사용 환경에 적합한 피로 저항 개선법을 제시하고, 크랙 발생 정도를 포함한 전자기기의 신뢰성 향상에 중요한 정보를 제공할 수 있을 것으로 기대한다.

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.

키워드

과제정보

이 연구는 금오공과대학교 대학 학술연구비로 지원되었음(2021)

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