Effect of Interface Strength on the Solder Joint Reliability of Flip Chip Packages

Tuskegee University, Tuskegee Institute AL

Investigators

Abstract

EEC-0002986 Mahfuz The PI's proposed to apply both the finite element and experimental methods to study the effect of underfill/die or underfill/substrate adhesion on the solder joint reliability of flip chip packages. This work will be a collaborative effort between researchers at the Tuskegee University Center for Advanced Materials and Auburn University Center for Advanced Vehicle Electronics. For the finite element methods, two conditions, namely, strongly-bonded and weakly-bonded interfaces will be considered. The weakly-bonded interface will be modeled using a set of gap elements at the interface. For modeling the strong interface, a common set of nodes will be employed at the interface which will be shared by both the constituent materials. Results for the die stresses at the underfill interfaces will be correlated with the test chip sensor measurements. Also, the cycles to failure of the solder joints will be predicted using finite element method due to cyclic thermal loads.