Maintenance of solder joints on the strength of simultaneously acting creep and fatigue phenomena by using microindentation technique

Last decades in reliability prototyping of microelectronic devices show that from a long time there is no good solution to examine it in relatively short time and small expenditure of costs. Currently all thermo-mechanical reliability processes are long-lasting and costly. With using only the most dominating failure mode and cyclic loadings tests can last for a number of months. Companies, which produce their products very fast can´t allow on such inconvenience, because this would lead to bankruptcy. To solve that kind of problem in this paper will be proposed new method of reliability investigating. Most of existing methods are concerned on only one failure mode which is dominating under selected loading conditions. Moreover all failure analysis are done under the simplified conditions what means that obtained results are not properly reliable. New presented method aim at using typical failure modes creep and fatigue at the same time while testing. That solution can have an important meaning in the standard Accelerated Thermal Cyclic test, which are based partly on experiment measurements and numerical analysis. Therefore appropriate understanding and development of analytical methods and experimental tools for multifailure criteria analysis could be very helpful. This work presents a methodology based on the use of well known indentation technique and second, innovative method with using new instrument called Failure And Reliability Investigation System created to study creep and fatigue phenomenon carried out on two lead-free alloys: SAC 405(S-SnAg4Cu0.5) and SAC 307(S-SnAg3Cu0.7).