Effect of curing conditions on the electrical properties of isotropic conductive adhesives composed of an epoxy‐based binder

Purpose – This paper investigates the variations in electrical properties of a typical isotropic conductive adhesive (ICA) made with an epoxy‐based binder that are caused by differences in the curing conditions.Design/methodology/approach – In‐situ monitoring of the various processes that were used to cure the ICA revealed that electrical conduction in the ICA specimens depends on both the high‐temperature curing conditions and the conditions during cooling to temperatures below the glass transition temperature (Tg).Findings – The electrical resistivity of the cured ICA specimens after cooling to ambient temperature decreased with increasing degree of conversion, tending towards a convergence value that decreased with increasing curing temperature. The electrical resistivity of the specimens also varied significantly depending on the subsequent annealing process. However, the electrical resistivity achieved after annealing at temperatures above the curing temperatures clearly depended on the particular cu...

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