CF4/O2 Plasma Accelerated Aluminum Metallization Corrosion in Plastic Encapsulated ICs in the Presence of Contaminated Die Attach Epoxies

Abstract

Corrosion rates, in autoclave, of aluminum bonding pad metallization in plastic encapsulated packages were studied as a function of die attach materials. The failure rate for chlorine contaminated die attach epoxies was enhanced if the pad metallization had prior exposure to carbon tetrafluoride/oxygen plasma. Eutectically attached devices exposed to CF4/O2 demonstrated increased failure rates. These rates were found to vary with length of exposure.