Accurate BGA Package Solder Joint Modeling for High Speed SerDes Interfaces

The solder joint of the ball grid array (BGA) package becomes a performance bottleneck as the serializer/deserializer (SerDes) speeds increase beyond 112 Gbps. This paper presents a comprehensive methodology to correctly model the volume and shape variations of solder joints for both nominal and worst-case electrical models. It is found that it is indispensable to accurately predict the performance of vertical transitions from package to board beyond 30 GHz. Construction of a worst-case solder joint model is also critical to ensure adequate electrical performance for a high-volume manufacturing solution.