Electrochemical Failures as a Function of Flux Volume Under Bottom Terminated Components

As electronics shrink and designs grow denser, Bottom Terminated Components (BTCs) introduce new reliability risks tied to flux residue volume, standoff gaps, and narrow pitches. These factors can trap active residues, block outgassing, and trigger dendritic growth, parasitic leakage, and electrochemical migration—all of which threaten long-term performance. Magnalytix’s study used custom QFN test vehicles and Surface Insulation Resistance (SIR) testing to demonstrate how pad design, pitch spacing, and flux volume directly affect electrochemical behavior. Results show that optimizing reflow profiles, pad geometries, and flux management significantly reduces the risk of failure, providing manufacturers with the data needed to design cleaner, more reliable assemblies.