Experimental system for analysing the combined loading and failure modes of solder joints in electronic packaging

Reliability of solder joints plays a major role in the electronic packaging. Indeed, the solder joints serve not only for the transmitting of electrical signals, but also for the heat transportation and as a structural support which is one of the most important aspects. Keeping of all these features is extremely difficult, due to different thermo-mechanical loadings, which cause slow degradation of the joints in the process of time. This paper will present preliminary results concerning an experimental method for testing the reliability of solder joints. This original method allows the precise separation of the selected degradation factors due to creep and fatigue. For this purpose the experimental setup and corresponding device (FRIS) have been developed and manufactured including displacement sensor of the micrometer order, which is mounted directly at the test sample. This allows both the measurement of the sample displacement submitted to two types of external thermomechanical loadings: - Creep resulting of constant loading applied over a long period of time, - Fatigue resulting from multicyclic loading. Additionally it is planned the application of these two types of loading in a form of a combined load in order to analyse and verify the influence of damage accumulation due to creep and fatigue solicitations on the solder joint behaviour. The above will be as well analysed by an appropriate FEM numerical modelling and simulation techniques.