A Solder Joint Fatigue Life Model for Combined Vibration and Temperature Environments

Electronic assemblies in field use are exposed to a wide range of environmental loads. The interaction of combined loads has to be considered in lifetime estimates of electronic packages. In this paper, we discuss lifetime prediction for lead-free soldered flip chips under vibration load in different temperature environments in terms of solder joint fatigue. Parameters for lifetime modeling are obtained from non-linear and temperature-dependent finite element analysis and lifetime experiments. We introduce temperature dependent coefficients and exponents for the Coffin-Manson-Basquin relationship considering elastic and plastic fatigue behavior. The results indicate that temperature is an important parameter affecting the solder joint vibration fatigue life.