Solder Joint Reliability: An integrated study of Electromigration, Thermal Migration and thermo-mechanical effects

Solder Joint Reliability (SJR) is the ability of solder joints to remain in conformance to their visual, mechanical and electrical specifications over a given period of time, under a specified set of operating conditions. There are various accelerated tests that can be performed to assess this. The focus of this research paper is confined to Electromigration, Thermal Migration and Temperature Cycling for Wafer Level Chip Scale Packaging (WLCSP). The goal of this study was to investigate what material sets gave the best SJR performance. It was discovered that a thicker UBM resulted in greater electrical and thermo-mechanical performance.