Robust design of third level packaging in portable electronics: Solder joint reliability under dynamic mechanical loading

Solder joint reliability issues that can be identified only at the system level are notoriously difficult to resolve in a timely manner using trial and error experimentation alone. The particular case of solder joint reliability of a side switch in a phone subjected to drop-impact is addressed. An approach employing response surface methodology (RSM) is proposed to solve reliability and robust design problems in advanced packaging. In particular, a lOx improvement in the drop test failure rate is demonstrated with a minimum of trial and error experimentation. Technical contributions are a) a novel drop life response function derived from strain energy principles, and b) an approach to address package reliability issues at the system level.