Scaling effects on grain size and texture of lead free interconnects - investigations by electron backscatter diffraction and nanoindentation

In this paper, the application of electron backscatter diffraction (EBSD) methods to solder interconnects is demonstrated, with particular emphasis on the effect of solder material volume on grain orientation, grain size and grain distribution in SnAg3.0Cu0.5 material, as well as with respect to the analysis of intermetallic compounds (IMC) formed in solder to board metallization interfaces. Investigations were carried out on solder spheres and solder interconnects between Cu/Sn or NiAu metallizations. It is shown, that the EBSD results derived allow to study the correlation between mechanical deformation properties, e.g. as characterized by nanoindentation testing, and microstructure in solder material in more detail which is of considerable significance for future improved reliability investigations.