Heating and reliability characteristics of electrically conductive adhesives using variable frequency microwave cure

Microwaves (MW) as heating source to cure polymer and polymer based composites can significantly speed up the curing process. Electrically conductive adhesive, (ECA) however, excludes the use of MW because metal particles contained inside the ECA will cause arcing when exposed to MW. A new technique named variable frequency microwave (VFMW) has recently been developed, with which arcing caused by the presence of metal can be avoided, and thus a rapid process for curing ECA is available with use of this technique. In this paper, several kinds of electrically conductive adhesives were cured with VFMW, and the heating rates as a function of the polymer material, the percentage of metal particles in the ECAs, the effect of geometric size and shape of the metal particles, and the physical parameters of the VFMW are reported. Then, reliability testing was conducted to analyze the reliability of the conductive adhesive-joint under VFMW curing conditions.