A Failure Analysis of a SOP IC Creep Corrosion on power module

Abstract

Creep corrosion classically happens on PCBs and PCBAs working in Sulfur-rich environment with humidity. Copper and silver metallization on PCB aand PCBA could be corroded by Sulfur-base gases. The associated corrosion products can creep to adjacent circuits, making electrical short failure of the system due to closely spaced metallized features on PCBs and PCBAs. This paper will introduce a novel creep corrosion failure of a SOP IC on power module. We found that a serial of flaws of the SOP package could be the original point of creep corrosion between adjacent pins. Finally, a serial of corrective methods was proposed to mitigate the creep corrosion problem on this SOP component.