The finite element analysis on reliability of gold bump

With the rapid development of Integrated Circuit, electrical performance requirement for packages is more and more stringent. In this situation, some research institutes proposed gold bump flip-chip packaging technology, which apply gold as bump material to achieve excellent electrical properties. In this paper, we used finite element analysis software to analyze the thermal mechanical stress and strain of gold bump flip chip under thermal cycling conditions, and we also predicted the fatigue life of the key joint depending on the fatigue life prediction equation. The results show that: during thermal cycling, the stress and strain of the outer side joints is larger, and failure will occur first at these joints; large stress concentration occurs at the position where the bump and the chip/substrate contact, and cracks easily occur at these parts. These conclusions will have great reference value to further technology research.