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

PI建议采用有限元和实验方法来研究下填料/模具或下填料/衬底粘附对倒装封装焊点可靠性的影响。这项工作将由塔斯基吉大学先进材料中心和奥本大学先进车辆电子中心的研究人员共同努力。对于有限元方法，将考虑两种条件，即强键合界面和弱键合界面。弱键界面将使用界面上的一组间隙元素来建模。为了对强接口建模，将在接口上使用一组公共节点，这些节点将由两个组成材料共享。下填料界面处的模具应力结果将与测试芯片传感器的测量结果相关联。此外，由于循环热载荷，将使用有限元方法预测焊点的失效周期。

EEC-0002986MahfuzThe 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.