Reliability analysis of low-Ag BGA solder joints using four failure criteria

摘要

The appropriate selection of failure criterion for solder joint studies is necessary to correctly estimate reliabilitylife. The objective of this study is to compare the effect of different failure criteria on the reliability life estimation.The four failure criteria in this study are a 20% resistance increase defined in the IPC-9701A standard, a resistancebeyond 500Ω, an infinite resistance (hard open), and a failure criterion based on X and R control charts.Accelerated thermal cycling conditions of a low-silver BGA study included 0°C to 100 °C with ten minute dwelltimes and -40°C to 125°C with ten minute dwell times. The results show that the life estimation based on X and Rfailure criterion is very similar to the life estimation when a 20% resistance increase defined in the IPC-9701Afailure criterion is used. The results also show that the reliability life would be overestimated if the failure criterionof a resistance threshold of 500Ω or an infinite resistance (hard open) is used.