Effect of filler geometry on the conduction of isotropically conductive adhesives

The effect of the geometry of conductive fillers on the conduction of conductive adhesives is studied. 3-D microstructure models of conductive adhesives are built to describe the positions and connections of the conductive fillers. Both rectangular flakes and spherical particles are studied. The total resistance of conductive adhesive is calculated by solving the resistor network formed by all particle connections. The method of full factorial design at two levels is used, and the geometric parameters are set at high and low level to study their effects on the resistivity of the conductive adhesive. Pareto chart of standardized effects of factors are examined for different configurations. Factors with significant effects are found. Main effect plots are used to study how significant factors affect the resistivity. Monte Carlo simulations are used for each configuration. Radius mean has the most significant effect for spherical particles, while the alignment angle is most significant for flakes.