|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Electronic Packaging and Interconnections
||Length scale dependent mechanical behaviour of elastically constrained Sn rich solder joints
||Anwesha Kanjilal, Praveen Kumar
|On-Site Speaker (Planned)
Mechanical behaviour of ductile metal layers confined between elastic substrates is influenced by constraints imposed by substrates, leading to pronounced size effects. This occurs in micro-bumps of Sn-rich solder/Cu joints having different form factor of ductile solder. In this study, the size effect was captured experimentally from tensile tests and creep tests on Sn-based solder/Cu joints, wherein systematic transition in tensile strength, overall creep rate and failure strain by necking and cavitation was observed as joint size decreased from 1mm to 150Ám. The role of geometric constraints was modelled using finite element analysis(FEA). A distinct difference was observed between experimental results and FEA as joint size reduced. This is attributed to size dependent microstructural effects which was further confirmed by EBSD and crystal plasticity(CP) modelling. Results from CP modelling agreed well with experimentally observed trend. Subsequently, the length-scale dependent mechanical behavior was quantified to predict the overall deformation of joints.
||Mechanical Properties, Characterization, Other