Electrical characterizations of isotropic conductive adhesives (ICAs)

Isotropic conductive adhesives (ICAs) have been developed as an alternative for traditional tin/lead (Sn/Pb) solders for electronics interconnect applications. Low processing temperature, elimination of lead, no-flux, no-clean process and the simple processing are some of the advantages of using ICAs. However, compared to the mature soldering technology, conductive adhesive technology is still in its infancy, and as such, there are some limitations for current commercial ICAs. Besides the conductivity fatigue and poor impact strength, electrically conductive adhesives tend to have lower current carrying capability and higher contact resistance in comparison to the conventional Sn/Pb solder. This is mainly due to the difference in the electrical conductive mechanisms between ICAs and Sn/Pb solders. This study focuses on current capacity measurements and other electrical properties, such as inductance, capacitance and resistance with a LCR meter and a four-point probe both in the direct current (DC) and alternating current (AC) ranges of the ICAs.