Risk analysis for CGA and advanced electronics packaging

This paper first presents packaging technology trends and accelerated reliability testing and life projection methods that are being practiced by industry. Specifically, it presents industry status on key advanced electronic packages, factors affecting accelerated solder joint reliability of area array packages and approaches for characterizations of assemblies under accelerated thermal loading. Examples on projecting cycles-to-failure (CTF) from one accelerated thermal cycle condition to another for column grid arrays (CGAs) also presented. It was shown, even for thermal cycling, the limitation of projection using mildly accelerated thermal CTFs to a more severe accelerated thermal CTFs, both for CGA assembled with eutectic tin-lead solder and ball grid array (BGA) Pb-free assemblies. Examples also given for projection life of complex spacecraft using accelerated testing and analysis; thereby, reducing risk. Quantitative assessments necessarily involve the mathematics of probability and statistics. In addition, accelerated tests need to be designed which consider the desired risk posture and schedule for particular project. Such assessments relieve risks without imposing additional costs and constraints that are not value added for a particular mission.