CAJ | 학술논문

以QFN封装1/4模型为研究对像，通过有限元分析及实验验证的方式，分析温度循环载荷下 QFN 器件焊点可靠性。有限元分析结果表明，QFN 的使用寿命周期为525周，其焊点应力的最大值位于拐角处的焊点上表面处，且应力值变化具有周期性，因此该位置上的焊点更容易出现失效。实验证实，温循载荷导致失效焊点内形成贯穿性裂纹，未失效焊点形成非贯穿性微小裂纹。失效焊点位置与有限元模拟结果吻合良好。
이QFN봉장1/4모형위연구대상，통과유한원분석급실험험증적방식，분석온도순배재하하 QFN 기건한점가고성。유한원분석결과표명，QFN 적사용수명주기위525주，기한점응력적최대치위우괴각처적한점상표면처，차응력치변화구유주기성，인차해위치상적한점경용역출현실효。실험증실，온순재하도치실효한점내형성관천성렬문，미실효한점형성비관천성미소렬문。실효한점위치여유한원모의결과문합량호。
QFN package possess good electric and thermolysis performance. Nevertheless, its package features result in it’s unable to release thermal stress. This paper found 1/4 of QFN package model, analysisng QFN’s joint reliability in the process of thermal cycling via finite element analysis and experimental verification. The result of FEA indicates that QFN service life is 525 cycles. Under thermal cycling loading, the maximum stress happened on top surface of joints which locate in the corner of chip, and stress is cycle in the process of thermal cycling, so those joints are more likely to be failure. Running through crack happened in failure joint which locate in the corner of chip due to thermal stress during thermal cycle process, there are many small cracks in other joints.