Epoxy/Ni adhesives can be used as integrated circuit (IC) packaging materials due to their lower cost than epoxy/Ag adhesives with acceptable electrical conductivity. In this study, epoxy/Ni adhesives were prepared and filled into multi-layer hole structures of novel design, a prototype of potential electronic components in circuit boards, to study effects of the hole structure geometry on a component's electrical resistance. Rheological behaviors at different conditions for capillary flows of highly filled epoxy/Ni suspensions, including stable and unstable (filtering and matting behaviors), chemorheological behaviors during processing and cure, and yield behaviors of moderately filled epoxy/Ni suspensions, were investigated to potentially relate to electrical conduction behaviors and processing of prototypes in generic circuits.; An empirical relationship between the contact resistance, hole diameter, and plate thickness was proposed, together with Ohm's law, to describe effects of the geometry on electrical resistance in generic circuits.; Stable and unstable capillary flows were investigated for highly filled epoxy/Ni systems with 75 wt% of different Ni particles. It was determined that, lower resin viscosity and shear rates enhance the flow instabilities and filtering of the polymer binder, and the pressure oscillation frequency and the average force increase with increasing shear rate. Incorporation of Ni nanopowders promotes a stable flow at similar filler concentrations, whereas occurrence of particle agglomerates somewhat nullifies this advantage, and leads to flow instabilities. Similar phenomena occur for adhesives during cure, and the rheological behavior changes as cure proceeds.; As an integrated circuit (IC) packaging material, chemorheological behaviors of electrically conductive epoxy/Ni adhesives were investigated. Strong nonlinearity and non-Newtonian flow behaviors were observed during cure. A comprehensive model, as well as its modified form, was proposed to describe the combined effects of the shear rate, resin conversion, filler volume fraction, and temperature on chemoviscosity.; Yield behaviors of moderately filled epoxy/Ni suspensions were studied at different conditions as well. Effects of the preshear, resin viscosity, temperature, particle size, as well as different methods for yield stress determination, were examined. Finally, the shear degradation of epoxy/Ni adhesives during cure was discussed.
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