The fatigue life analysis of conductive adhesive

Considering the influence of the cost, reliability and environment issues, the lead-free material of solder connection is paid more and more attention in integrated circuit packaging field. As the substitute of traditional solder, conductive adhesive has its own advantages. In this paper, a ball grid array (BGA) is chosen to illustrate the fatigue model for the methods of strain-based and energy-based life prediction. The strain analysis theory and the finite element analysis (FEM) simulation of fatigue life prediction are introduced in this paper. The conductive adhesive´s failure mechanism of theoretical analysis is described. By means of finite element analysis, thermal stress simulation curve of conductive adhesive is analysed. The curve (s-n curve) of conductive adhesive fatigue life and load amplitude as well as fatigue sensitivity coefficient is given. And failure of life under different stress is predicted. Finally, the outlook of conductive adhesive connection reliability is also expounded.