Computational model validation with experimental data from temperature cycling tests of PBGA assemblies for the analysis of board level solder joint reliability

A previous experimental study was conducted to characterize the thermal fatigue life of PBGA solder joints under temperature cycling condition. The temperature cycling profile was one-hour cycles with a temperature range from -40°C to 125°C. The thermal cycling test lasted for more than 3,000 cycles and the Weibull characteristics were obtained. In the present study, a computational model is established for the analysis of solder joint thermal fatigue life. The current approach is a finite element based analysis and the previous experimental data are used for model validation. In this paper, the results from two types of plastic ball grid array assemblies are presented. Both eutectic Sn-Pb and Pb-free solders are studied. The comparison between computational and experimental results shows that the two dimensional finite element analysis appears to be sufficient for estimating the thermal fatigue life of solder joints in plastic ball grid array assemblies.