Vibrations in the Flip-Chip Soldering Process

General results are presented for the dynamics of all six degrees of freedom of a rigid flip-chip device connected by an array of melted solder joints to a substrate subjected to small stationary random accelerations. The solder joints are modeled as dissipative fluid members which develop a linear restoring force when displaced in the horizontal or vertical directions. The parameters for this model (stiffness and damping of the melted joints) are obtained experimentally by measuring the resonant behavior of a device oscillating in the out-of-plane direction. A quantitative model is constructed for an arbitrary device for the statistics of the translational degrees of freedom, rotational degrees of freedom, and solder joint deformations.