MLC Capacitor Failure Analysis (MLCC)

Gideon Analytical Labs received one failed multilayer ceramic capacitor for failure analysis. The image below is from Wikipedia. It shows the standard metallurgy for MLCCs.

The capacitor was mounted to the PCB and showed no signs of external damage. The capacitor was removed from the PCB and tested. The leakage current was too high for a capacitor of this size. The capacitor failure analysis revealed by a cross-section that the capacitor had thermal cracks extending from one side to the other. These types of cracks are caused by excessive heat either by the circuit or the soldering process. It was late found that the crack was caused by an operator installing the MLCC to the PCB because it was reworked. A video of how these MLCCs are made can be seen at the following link.  $2 Gideon Analytical Labs can find the problem quickly so that corrective action can be made promptly. If you need failure analysis on capacitors, call us at 845-255-5356.