Experimental and Numerical Analysis of Melting and Solidification of SnAgCu Joints

One of the most vulnerable components of electronic circuits is the solder joints. The most common technique of soldering used in electronics is the reflow soldering. During the soldering process, different issues may occur leading to the inception of some defects (tombstone effect, flux spattering, etc.). To avoid these defects, it is mandatory to follow the parameter values of the reflow process, especially temperature values. In this paper, the temperature distribution for three types of samples (two interconnected soldering pads-without solder, with solder on one pad, and with solder on both pads) during the reflow soldering process, calculated with Comsol Multiphysics software (heat transfer 3-D module) is presented. The calculated values are then compared to the ones obtained by experiments in order to verify the accuracy of the numerical model. To carry out the computations, the latent heat of melting/solidification and the variation with the temperature of the solder parameters were considered. The results show that there is a good correlation between the measured and calculated values, the differences (for all types of samples) being lower than ±3 °C.