Thermo-Mechanical Deformation Analysis of Flip-Chip Packages(Electronic Devices)

Abstract

Moire interferometry technique was applied to the thermo-mechanical analysis of flip-chip packages. Thermal deformations of two kinds of flip-chip structures, no-underfill and underfill flip-chip packages, were studied. The differences of the thermal deformations between the two packages were measured to clarify the effect of underfill. The experimental results showed that the underfill plays an important role to give similar curvatures at the lower side of the silicon chip and the upper side of the substrate. The shear deformation of the solder ball decreased due to the underfill, while the tensile deformation increased.