Reliability improvement of conductive adhesives on tin (Sn) surfaces

Effective organic corrosion inhibitors are introduced into a typical electrically conductive adhesive (ECA) formulation and evaluated. With the incorporation of small amounts of these additives, lower bulk resistivity and highly stable contact resistance on tin (Sn) surfaces were achieved. Contact angle, grazing angle Fourier Transfer Infrared (FT-IR) spectroscopy and X-ray Photoelectron Spectroscopy (XPS) characterizations showed the presence of coatings of the corrosion inhibitors on the metal surfaces. A barrier passivation layer formed on Sn surfaces with the effective corrosion inhibitors. X-ray diffraction analysis confirmed that such a passivation layer protected the Sn surface and prevented oxidation and corrosion under elevated temperature and humidity environment.