Many electronic circuits use capacitors for charge buffering and timing applications.  The Multi-layer Ceramic Capacitor (MLCC) is the most commonly used capacitor for surface mount circuits.  Thermal shock encountered by MLCCs during the wave soldering operation is responsible for yield losses greater than 0.1% industry wide [Danford, A., 1988].  The sudden exposure of the capacitor to high temperature produces large temperature gradients in the capacitor, resulting in high stresses.  These stresses are induced by the mismatch of mechanical and thermal properties of the constituent materials of the MLCC.  Stress cracking results from the inability of the MLCC to absorb these stresses and is aided by manufacturing defects like delaminations, voids and inclusions that provide ready paths for crack initiation and propagation.  Various efforts have been made to study the factors driving the generation of stresses in the MLCC during the wave soldering process.
 

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