High temperature deformation of high density interconnects and packages by moire interferometry/FEM hybrid method

In the current study, 1200 I/mm grating or 600 1/mm gratings are replicated at either 80/spl deg/C or 160/spl deg/C onto the cross sections of several high density area interconnects and packages. These packages include BGA, flip-chip, and glob-top packages. The specimens are measured at room temperature for the thermal deformation induced by the cooling process. The strain distributions inside the solder joints are analyzed by both the moire interferometry and experimental/FEM hybrid method. Warpage of the packaging systems was measured and the effects of the bonding, encapsulation, soldering, and geometry on the deformation are discussed.