Prediction studies on percolation threshold behaviour of silver filled epoxy composite for electrically conductive adhesives applications

Electrically conductive adhesives (ECAs) has received considerable interest as a solder replacement in flip chip packaging because of their advantages such as significant reduction in pitch, weight and volume and increased environmental compatibility. Conductivity of the ECA polymers can be described by percolation threshold which can be achieved by the addition of silver (Ag) nanoparticles in polymer matrix. In this present study, the existing electrical conductivity models were used to predict the percolation threshold phenomena in the conductive polymer composites. The electrical property characterization was modelled by finite element and statistical approach that assumes the transition of insulator to conductor at certain filler content. The model was developed based on spherical shape of Ag filler. From the study, it was found that the electric field and current density forces of spherical particles are governed by a dispersion of particle in the polymer matrix and filler content.