Solder paramater sensitivity for Package-on-Package (POP) on fatigue life prediction

Abstract

Due to requirements of cost-saving and miniaturization, Package-on-Package (PoP) has recently gained popularity in many applications. However, its board level solder joint reliability during the thermal cycling test is not as well-studied as common single die BGA.. In this research, solder joint fatigue life of PoP is analyzed in detail. 3D model is established for PoP by using ABAQUS design software with consideration of detailed design, realistic shape of solder ball and non-linear material properties. The fatigue model is based on the Hyperbolic Sine Creep Model and it is taken from the works of Park,Hong and Lau. [1] The critical solder ball is observed located at the inner ring of bottom solder balls which is in between SPBGA and test board. The results show that in general, solder ball diameter has no much effect on its fatigue life..