Electrical characterizations and considerations of electrically conductive adhesives (ECAs)

Electrically conductive adhesives (ECAs) have been developed as an alternative for traditional tin/lead (Sn/Pb) solders for electronic interconnect applications. The low processing temperature, the elimination of lead, the no-flux, no-clean process and the simple process are some of the advantages of using ECAs. However, compared to the mature soldering technology, conductive adhesive technology is still in its infancy, as such, there are some limitations for current commercial ECAs. In addition to the conductivity fatigue and poor impact strength, electrically conductive adhesives tend to have lower current carrying density as compared to the conventional Sn/Pb solder. This is mainly due to the difference in the electrical conductive mechanisms of ECAs. Generally speaking, ECAs have high contact resistance than metallurgical solders. As such, high frequency and high power devices may require high current density and high performance ECAs. In this paper, we will focus our study on current capacity measurements and other electrical properties, such as inductance, capacitance and resistance with the LCR meter and the four point probe both in the DC and AC ranges of the ECAs. Furthermore, we will discuss the electrical performance of these ECAs for the high performance electronic applications.