Comparative characterization of chip to epoxy interfaces by molecular modeling and contact angle determination

An investigation of interfacial interaction has been performed between three epoxy molding compound materials and a native silicon dioxide layer (SiO 2) usually found at chip surfaces. The epoxy materials were an industry oriented epoxy molding compound Epoxy Phenol Novolac (EPN), its filled variety EPN F (with silica particles) and a model aromatic epoxy 1 (2 1 2). All systems are described in full in [1] and [2]. The free surfaces of the solid materials were experimentally analyzed by contact angle measurements of three different liquids (water, methylene-iodide (MI) and glycerol). Results are compared to interfacial energies obtained by analysis of the interfaces in bimaterial molecular models, yielding reasonable agreement. A qualitative prediction regarding the influence of water on the interfacial strength between chip and molding compound is attempted.