The popcorning effect of plastic ball grid array (PBGA) packages is analyzed using the method of fracture mechanics. The following three specific problems are studied: (1) crack initiation in the die attach of the package, (2) crack growth in the die attach, and (3) crack growth at the interface between the solder mask and copper. Two different methods (crack tip opening displacement and virtual crack closure technique) are used to determine the crack-tip parameters such as the strain energy release rate, stress intensity factors, and phase angle for different crack lengths and temperatures.
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