Development of Constitutive Equations and Novel Methodology for Failure Prediction Models for SAC Lead-free Alloys

Abstract form only given. One of the big challenges today for the electronic packaging industry is to implement lead free solder replacing Pb-Sn solder alloy. This impacts the entire electronic manufacturing industry, from component supplier to equipment manufacturer. Though the industry has identified possible alternates to Sn/Pb solder alloy, much work still needs to be done, especially in the area of component & board level reliability, assembly process development, and characterization of the alloys including development of "constitutive equations" and "failure life prediction model." In this presentation, the study to establish material constitutive relationship and failure prediction model for Sn-Ag-Cu lead free solder alloys will be discussed. Experimental studies are conducted to get solder material properties and characteristic fatigue life of the lead free solder joint by running package and board level accelerated tests. Based on material test and fatigue test results a material constitutive and a failure life prediction model will be developed. Those models will be incorporated in the finite element simulation for computational analysis to predict the solder joint reliability. Also those models will be validated with other lead free solder joints models for lead free solder joint reliability