Failure analysis of a second level electronic package

A 2^nd level electronic package was fabricated using a die, polymer based epoxy and gold wire bonds. This package was subjected to reliability testing to gauge its reliability under extreme operating conditions, with the temperature raised to a constant 85°C, and 85% humidity for 300-400 hours to simulate transport conditions and operation in consumer electronics. The reliability is determined via measuring the resistance value between the conducting lines in the package for a set period of time. After the allotted time, the package was removed from the chamber, sectioned and observed under a light optical microscope (LOM). It was determined that the die was corroded, and the epoxy seal was filled with voids, resulted from the popcorn effect. It was concluded that electronic packaging is prone to failures such as corrosion, popcorn effect, and degradation of wire bonds that will shorten the actual operational lifespan of the component.