Solder joint reliability in automotive applications: describing damage mechanisms through the use of EBSD

Due to the large scatter in data that have been gathered over the past years to describe the reliability behavior of lead-free solder joints, a precise correlation of aging condition to the resulting damage appearance could not yet be established. Recent research has shown, that a key to a more profound understanding of damage mechanisms can be offered through the analysis of recrystallization processes in the solder joints. Electron Backscatter Diffraction (EBSD) is a valuable analysis method to obtain quantitative data on grain properties. In this paper the results of detailed EBSD measurements on SnAg3.0Cu0.5 solder joints of chip resistors are therefore presented. Correlations between recrystallization behavior and applied loading profile are generated and verified through FEM-simulations. It is recommended to employ sophisticated data mining tools like Support Vector Machines to support data interpretation of the various parameters offered by EBSD.