Novel test concept for experimental lifetime prediction of miniaturized lead-free solder contacts

The paper presents the method of generating lifetime-prediction-laws on special prepared specimen. The combination of thin- and thick-film technology allows building up test probes very similar to electronic packages including the measurement issues. Influences of pad surface metallurgy, microstructure of solder and in eutectic solder alloys are regarded. The investigation objects provide monitoring of electrical and mechanical damage process of SnAgCu-solder bump. Different thermo-mechanical loads are applied in ranges of 0degC to +80degC, -20degC to +90degC, -40degC to +125degC and -50degC to + 150degC. The results of these tests and give universal lifetime-prediction laws for SnAgCu base solder joints. Main goals are to find coefficients for lifetime prediction models of lead-free SAC-solder. One issue points on the Coffin-Mason relation, which can be used in common FEM-tool. The other problem employs the empirical model of Norris-Landzberg relation