Growth kinetics of interfacial damage: Epoxy coating on a generic dual inline package

Epoxy coated dual inline packages (DIPs) consisting of 24 pins and three pa rallel gold metallization lines were used as test vehicles in accelerated e nvironmental tests. The coated DIPs were subjected to 121 degreesC, 100% re lative humidity, and unbiased conditions as a standard test condition. Afte r each test, optical microscopy was performed to monitor the interfacial da mage. Changes in the leakage current also were monitored for correlation wi th measured interfacial damage. The growth of interfacial damage as a funct ion of time was observed over the entire surface area of each DIP. Each dam age site on the interface was monitored in an effort to model the evolution of the geometrical features and magnitude of the damage. It was noted that a two-parameter Frechet cumulative distribution function (edf) could be us ed to represent the damage growth at each time interval. Precipitate in typ ical damage locations also was analyzed and found to consist primarily of s odium, carbon, and oxygen. The growth kinetics of interfacial damage, inclu ding the location and magnitude of the damage, is characterized, and the do minant failure modes are identified for this type of protective coating.