Journal of the Microelectronics and Packaging Society (마이크로전자및패키징학회지)

The Korean Microelectronics and Packaging Society (한국마이크로전자및패키징학회)
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Analysis on the Thermal Deformation of Flip-chip Bump Layer by the IMC's Implication

IMC의 영향에 따른 Flip-Chip Bump Layer의 열변형 해석

  • Lee, Tae Kyoung (Education program for samsung advanced integrated circuit, Pusan National University) ;
  • Kim, Dong Min (Education program for samsung advanced integrated circuit, Pusan National University) ;
  • Jun, Ho In (Education program for samsung advanced integrated circuit, Pusan National University) ;
  • Huh, Seok-Hwan (SEMCO ACI Division) ;
  • Jeong, Myung Young (Department of Cogno-Mechatronics Engineering, Pusan National University)
  • 이태경 (부산대학교 차세대전자기판회로학과) ;
  • 김동민 (부산대학교 차세대전자기판회로학과) ;
  • 전호인 (부산대학교 차세대전자기판회로학과) ;
  • 허석환 (삼성전기(주)) ;
  • 정명영 (부산대학교 인지메카트로닉스공학과)
  • Received : 2012.09.03
  • Accepted : 2012.09.27
  • Published : 2012.09.30
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Abstract

Recently, by the trends of electronic package to be smaller, thinner and more integrative, fine bump is required. but It can result in the electrical short by reduced cross-section of UBM and diameter of bump. Especially, the formation of IMCs and KV can have a significant affects about electrical and mechanical properties. In this paper, we analyzed the thermal deformation of flip-chip bump by using FEM. Through Thermal Cycling Test (TCT) of flip-chip package, We analyzed the properties of the thermal deformation. and We confirmed that the thermal deformation of the bump can have a significant impact on the driving system. So we selected IMCs thickness and bump diameter as variable which is expected to have implications for characteristics of thermal deformation. and we performed analysis of temperature, thermal stress and thermal deformation. Then we investigated the cause of the IMC's effects.

최근 전자 제품의 소형화, 박형화 및 집적화에 따라 칩과 기판을 연결하는 범프의 미세화가 요구되고 있다. 그러나 범프의 미세화는 직경 감소와 UBM의 단면적 감소로 인하여 전류 밀도를 증가시켜 전기적 단락을 야기할 수 있다. 특히 범프에서 형성되는 금속간화합물과 KV의 형성은 전기적 및 기계적 특성에 큰 영향을 줄 수 있다. 따라서 본 논문에서는 유한요소해석을 이용하여 플립칩 범프의 열변형을 분석하였다. 우선 TCT의 온도조건을 통하여 플립칩 패키지의 열변형 특성을 분석한 결과, 범프의 열 변형이 시스템의 구동에 큰 영향을 미칠 수 있음을 확인하였다. 그리고 범프의 열변형 특성에 큰 영향을 미칠 것을 생각되는 IMC층의 두께와 범프의 직경을 변수로 선정하여 온도변화, 열응력 및 열변형에 대한 해석을 수행하였으며, 이를 통하여 IMC층이 범프에 영향을 미치는 원인에 대한 분석을 수행하였다.

Keywords

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