Solder Fatigue Analysis of a Chip Package Ball Grid Array (BGA) 

DRD performed this analysis for a major computer network equipment manufacturer. The objective of this analysis was to determine whether or not solder balls will fail when the package is subjected to thermal cycling. DRD used both quarter and 3D slice models. DRD used ANSYS Parametric Design Language to construct these model so that design changes can easily be made. The model accounts for viscoplastic behavior in the solder material, temperature-dependent plasticity in the copper pads, temperature dependent and orthotropic material properties in the PCB, and other material models as DRD deemed appropriate.

 

Quarter Model of the PCB, Copper Pads, Solder Balls, and Substrate

 


This graphic shows the total strain in the
worst solder ball.


This graphic shows the plastic zone in red
in the worst solder ball.

This graphic shows the creep
strain in the worst solder ball.