Anisotropic conductive adhesive film(ACF) is chosen to substitute for Sn/Pb solder and applied to microelectronic packaging.In this thesis,ACF is composed of polystyrene microspheres(PSt)(3~5 μm) plated with a thin Ni particles(1~2 μm) outside and a special epoxy resin.Both of them are mixed to be ACF.Electronic conductive attributes and corrosive resistance behavior of ACF are analyzed by alternating current impedance measurement and potentiodynamic polarization under highly thermal humid conditions.The results show that after aging 4 h in 80 ℃ and 85% RH condition,contact resistance of ACF increases greatly,and the main reason is the oxidation formation of Ni prevents electric current from going through.Furthermore,the effect of temperature on corrosive behavior of ACF exceeds the effect of humidity,and both of them accelerate the failure of ACF reliability in microelectronic interconnection.Corrosion resistances of ACF are better than that of Sn37Pb solder in the same case.The possible reason is that Ni is protected by the base epoxy resin,and dispersion of corrosive medium into adhesive interlayer is held back.