The preparation process of electrically conductive filler for anisotropic conductive adhesive was performed and discussed.The spherical filler contains tri-layer structures: resin core,Ni-P intermediate coating layer,Au outer coating layer.The 4 μm resin spherical cores were synthesized by monodispersion polymerization method.Then they were contributed to electrical conductivity by electrolessly plating Ni-P layer and gold layer.These particles have good corrosion resistance,high stability,and enough mechanical strength.When mixed with thermosetting epoxy resin to produce anisotropic conductive adhesive(ACA),it can realize a good conductive bonding between bumps on dies and pads on substrates.This environmentally friendly conductive material offers numerous advantages over conventional solder technology and is an ideal substitute for the lead-contained solder in electronics packaging.
