FEA modeling of FCOB assembly solder joint reliability

A methodology was developed for correlating Thermal Cycling (TC) and Thermal Shock (TS) tests and failure prediction for solder joints in a FCOB assembly. TC and TS tests are used to assess the long-term reliability performance of flip-chip solder interconnections. Non-linear Finite Element Analysis was used to model and simulate TC and TS loading conditions for the FCOB assembly. Temperature and Strain-rate dependent properties for solder and frequency-modified low cycle fatigue relationships were employed in this study. The FEA and fatigue life prediction results were compared to actual reliability test results for FCOB assembly. The failure prediction results are able to give the correct trend as seen in the test results where a shorter fatigue life was predicted for TC test and longer fatigue life was recorded for TS test condition.