In this work a new type of isotropically conductive adhesive (ICA) for microelectronic applications is presented. An extremely low value of ionic impurity content in the ICA is realized by using a cycloaliphatic epoxy resin. The intrinsically brittle behaviour of this type of resin has been counterbalanced by introducing porous silver nanopowders as a conductive filler material instead of conventional silver flakes. In this way a considerable reduction of metal filler content is achieved at still acceptably low values of the electrical resistivity. It is shown that the mechanical properties under shear loading is improved considerably, when using the nanopowder/epoxy composites as compared to ICA's based on Ag flakes. Therefore this new ICA is particularly suited for bonding substrates and components, which differ strongly with respect to their coefficient of thermal expansion.
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