Investigation on soldering reliability in terminal electrodes of MLCC

Plating permeation in the process of nickel and tin electroplating greatly reduced soldering reliability of products and drawn particularly attention from MLCC manufacturers. Based on the results of SEM and EDS analysis, it indicated that the silver end terminations spread from edges to middle in the surface of ceramic body in sintering process, and formed a 100 μm width transition areas near silver end terminations where there existed a great deal of silver paste components. This improved the conductivity of ceramic body of this region, which facilitated deposition of plating metal and led to the plating permeation. On the contrary, there was no special area near end termination in control samples. The investigation suggests that capillarity induced by loose and porous surface of experiment samples facilitated the permeation and extension of silver paste on the surface of the ceramic body.