Journal of the Microelectronics and Packaging Society (마이크로전자및패키징학회지)

The Korean Microelectronics and Packaging Society (한국마이크로전자및패키징학회)
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Encapsulation of an 2-methyl Imidazole Curing Accelerator for the Extended Pot Life of Anisotropic Conductive Pastes (ACPs)

이방 도전성 페이스트의 상온 보관성 향상을 위한 Imidazole 경화 촉매제의 Encapsulation

  • Kim, Ju-Hyung (Department of Materials Science & Engineering, Seoul National University of Science & Technology) ;
  • Kim, Jun-Ki (Advanced Welding & Joining Technology Center, Korea Institute of Industrial Technology(KITECH)) ;
  • Hyun, Chang-Yong (Department of Materials Science & Engineering, Seoul National University of Science & Technology) ;
  • Lee, Jong-Hyun (Department of Materials Science & Engineering, Seoul National University of Science & Technology)
  • 김주형 (서울과학기술대학교 신소재공학과) ;
  • 김준기 (한국생산기술연구원 용접접합연구센터) ;
  • 현창용 (서울과학기술대학교 신소재공학과) ;
  • 이종현 (서울과학기술대학교 신소재공학과)
  • Received : 2010.12.08
  • Accepted : 2010.12.16
  • Published : 2010.12.30
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Abstract

To improve the pot life of one-part in-house anisotropic conductive paste (ACP) formulations, 2-methyl imidazole curing accelerator powders were encapsulated with five agents. Through measuring the melting point of the five agents using DSC, it was confirmed that a encapsulation process with liquid-state agents is possible. Viscosity of ACP formulations containing the encapsulated imidazole powders was measured as a function of storage time from viscosity measurements. As a result, pot life of the formulations containing imidazole powders encapsulated with stearic acid and carnauba wax was improved, and these formulations indicated similar curing behaviors to a basic formulation containing rare imidazole. However, the bondlines made of these formulations exhibited low average shear strength values of about 37% level in comparison with the basic formulation.

본 연구에서는 일액형 이방 도전성 페이스트(anisotropic conductive paste, ACP) 혼합 조성의 상온 보관성을 향상시키기 위해 2-methyl imidazole 경화 촉매제를 5종의 각기 다른 물질로써 encapsulation하였다. Encapsulation용 분말 물질들은 DSC를 통해 그 융점을 관찰하였으며, 이를 통해 encapsulation용 분말 물질들을 액상으로 용융시켜 encapsulation하는 공정이 가능함을 확인할 수 있었다. Encapsulation된 2-methyl imidazole 분말을 포함한 ACP 혼합물질의 상온 보관성을 평가하기 위하여 시간에 따른 점도 변화가 관찰되었다. 그 결과, stearic acid와 carnauba wax로 encapsulation된 2-methyl imidazole 분말을 포함한 혼합물질에서 향상된 상온 보관성을 관찰할 수 있었으며, 이러한 formulation은 기본 혼합물질과도 유사한 경화 거동을 보임을 확인할 수 있었다. 최종적으로 stearic acid와 carnauba wax로 encapsulation된 2-methyl imidazole 분말을 포함한 혼합물질을 사용하여 RFID 칩을 제조된 안테나 패턴이 형성된 PET 기판에 고속 플립칩 본딩을 실시하였다. 이 경우 측정된 접합 강도는 기본 혼합물질에 비해 약 37%의 수준인 것으로 측정되었다.

Keywords

References

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